Unit BCM2708
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Description
Ultibo BCM2708 interface unit
This unit provides the BCM2708 specific implementations of the following devices:
- SPI0
- I2C0
- I2C1
- SPI1
- SPI2
- I2C Slave
- SPI Slave
- DMA
- PWM0
- PWM1
- PCM
- GPIO
- UART0
- UART1
- SDHCI (eMMC)
- Clock
- ARM Timer
- Random
- Mailbox
- Watchdog
- Framebuffer
- MIPI CSI-2 (Camera Serial Interface)
- DSI (Display Serial Interface)
BCM2708 SPI0 Device
The BCM2708 has a single master mode SPI controller that supports 3 wire, 2 wire and LoSSI modes of operation. It also has 2 auxiliary SPI masters which do not support DMA mode (see SPI1/2 below).
The main SPI0 controller supports polled, interrupt and DMA modes and includes 3 chip selects although only CS0 and 1 are available on the 26 or 40 pin header.
By default SPI0 can appear on GPIO pins 7 to 11 (CS1, CS0, MISO, MOSI, SCLK) using alternate function 0 or on GPIO pins 35 to 39 (CS1, CS0, MISO, MOSI, SCLK) using alternate function 0, only pins 7 to 11 are available on the header.
BCM2708 I2C0/1 Device
The BCM2708 has 3 Broadcom Serial Controller (BSC) devices which are fast mode (400Kz) masters numbered BSC0, BSC1 and BSC2.
Device BSC2 is dedicated to the HDMI interface and is not availale for use by the ARM processor. All BSC devices contain a 16 byte FIFO, support 7 bit and 10 bit addressing and have software configurable clock timing.
By default BSC0 can appear on GPIO pins 0 and 1 (Alternate function 0), 28 and 29 (Alternate function 0) or 44 and 45 (Alternate function 1). Unfortunately on all except the Revision 1 models none of these pins are available on the 26 or 40 pin header.
Note: On the Raspberry Pi A+/B+/Zero/2B/3B the ID EEPROM pins on the 40 pin header are actually connected to GPIO 0 and 1 (BSC0)
Device BSC1 can appear on GPIO pins 2 and 3 (Alternate function 0) or 44 and 45 (Alternate function 2) but only pins 2 and 3 are exposed on the 26 or 40 pin header.
BCM2708 SPI1/2 Device
The BCM2708 has 2 additional SPI universal masters available as part of the AUX device which support interrupt mode but not DMA and therefore only allow limited bandwidth transfers due to the CPU overhead required to sustain high data rates.
Both devices support 3 chip selects, by default SPI1 is available on GPIO pins 16 to 21 (CS2, CS1, CS0, MISO, MOSI, SCLK) using alternate function 4 and SPI2 is available on GPIO pins 40 to 45 (MISO, MOSI, SCLK, CS0, CS1, CS2) using alternate function 4. Only pins 16 to 21 are available on the header and only on the 40 pin header of the Raspberry Pi A+/B+/Zero/2B/3B.
BCM2708 DMA Device
The DMA controller has 16 channels in total although not all are available for software to use as some are already used by the GPU.
The firmware will pass the value dma.dmachans on the command line which will indicate which channels are available for our use.
Channels 0 to 6 are normal channels which support 2D stride and transfers up to 1GB per control block
Channels 7 to 14 are Lite channels which do not support stride and only allow transfers up to 64KB per control block
Channel 15 is not mentioned in most documentation and is shown as not available in the mask passed in dma.dmachans
Channel 0 and 15 are Bulk channels which have an additional FIFO for faster transfers (8 beat burst per read)
BCM2708 PWM0/1 Device
The BCM2708 has a single PWM controller with 2 independent output bit streams with multiple algorithms for generating the output pulse. The PWM controller supports either a single data register (independent per channel) or a 16 x 32 FIFO which also supports DMA mode transmission.
On the Raspberry Pi PWM0 and PWM1 are also connected via GPIO pins 40 and 45 (40 and 41 on the Raspberry Pi 3B) to the audio circuit and allow playback of digital audio signals via the 3 or 4 pole line jack (depending on model).
PWM0 is available on GPIO pins 12 (function 0), 18 (function 5), 40 (function 0) and 52 (function 1).
PWM1 is available on GPIO pins 13 (function 0), 19 (function 5), 41, 45 (function 0) and 53 (function 1).
On the Raspberry Pi A and B only pin 18 is exposed on the 26 pin header.
On the Raspberry Pi A+/B+/Zero/2B/3B pins 12, 18 and 19 are exposed on the 40 pin header.
BCM2708 GPIO Device
The GPIO has 54 pins available each with multiple alternate functions. All pins can be configured as input or output and all can have pull up or down applied.
Not all pins are exposed on the 26 or 40 pin header of the Raspberry Pi, for details of which pins are available see:
Raspberry Pi A and B - https://www.raspberrypi.org/documentation/usage/gpio/README.md
Raspberry Pi A+/B+/2B/3B/Zero - https://www.raspberrypi.org/documentation/usage/gpio-plus-and-raspi2/README.md
Some of the 54 pins are used for peripheral communication (such as the SD card) and are not available for general use,take care when changing function selects on pins to avoid disabling certain system peripherals.
Event detection can be enabled for both high and low levels as well as rising and falling edges, there is also an asynchronous rising or falling edge detection which can detect edges of very short duration.
BCM2708 UART0 Device
The UART0 device is an ARM PL011 UART which supports programmable baud rates, start, stop and parity bits and hardware flow control and many others. The UART0 is similar to the industry standard 16C650 but with a number of differences, the PL011 has a some optional features such as IrDA, Serial InfraRed and DMA which are not supported by the Broadcom implementation. In the standard configuration the UART0 TX and RX lines are connected to GPIO pins 14 and 15 respectively (Alternate function 0) but they can be remapped via GPIO function selects to a number of other locations. On the Raspberry Pi (all models) none of these alternate pin mappings are exposed via the 26 or 40 pin header and therefore cannot be used easily. This means that UART0 and UART1 cannot be used at the same time.
On the Raspberry Pi 3B the UART0 can be mapped to GPIO pins 32 and 33 (Alternate function 3) to communicate with the built in Bluetooth module.
BCM2708 UART1 Device
The UART1 device is a Broadcom implementation that is part of the AUX device which also includes the SPI1 and SPI2 devices. This device is termed a Mini UART and has a smaller feature set than the PL011 UART but still supports a fairly standard communication protocol with programmable baud rate and hardware flow control.
The Mini UART is similar to the standard 16550 device but is missing some of the features, the device also has no DMA support so high speed transfers will produce a higher CPU load. In the standard configuration the UART1 TX and RX lines are connected to GPIO pins 14 and 15 respectively (Alternate function 5) but they can be remapped via GPIO function selects to a number of other locations. On the Raspberry Pi (all models) none of these alternate pin mappings are exposed via the 26 or 40 pin header and therefore cannot be used easily. This means that UART0 and UART1 cannot be used at the same time.
On the Raspberry Pi 3B the UART1 can be mapped to GPIO pins 32 and 33 (Alternate function 5) to communicate with the built in Bluetooth module.
BCM2708 SDHCI Device
The SDHCI controller on the BCM2708 is an Arasan SD Host controller.
The Card Detect pin is connected to GPIO pin 47 (on the RPi Model A/B)(Not connected on the RPi Model A+/B+)
The Write Protect pin is not connected on any RPi model.
BCM2708 Clock (System Timer) Device
The clock device in the BCM2708 is based on the System Timer which is a 64 bit free running counter that runs at 1MHz regardless of core or CPU clock speeds. The System Timer cannot be stopped and the counter cannot be set or reset.
The System Timer includes 4 compare registers which can each generate an interrupt when the compare value is matched, however 2 of the 4 are consumed by the GPU and on the Raspberry Pi A/B/A+/B+/Zero the other 2 are used for the scheduler and clock interrupts in Ultibo.
This device simply exposes the free running counter as a clock value and does not provide access to the timer compare functionality or to interrupt based events, for those see the timer devices below.
BCM2708 Clock (ARM Timer) Device
This device represents that free running counter from the ARM Timer device (below) as a clock device. The free running counter does not appear in the original SP804 timer. The counter is 32 bits wide and has its own divider that is 8 bits wide meaning that it can be set to clock rates of between 975KHz and 250MHz (or 1.5MHz to 400MHz on the Raspberry Pi 3B).
The counter does not generate an interrupt and cannot be set or reset but it can be stopped and started.
BCM2708 ARM Timer Device
The ARM Timer device in the BCM2708 is based on the ARM SP804 timer with some modifications and additions. In the Raspberry Pi it is connected to the core clock which by default is 250MHz but was increased to 400MHz on the Raspberry Pi 3B.
The divider is 10 bits wide which means that the ARM Timer can be set to clock rates of between 250KHz and 250MHz (or 400KHz to 400MHz on the Raspberry Pi 3B). Both the counter and the load/reload value are 32 bits wide by default giving a wide range of tick intervals.
The ARM Timer features a free running counter which is not enabled or used by this driver and a down counter which operates in wrapping mode so that each time it reaches 0 it triggers an interrupt and reloads the value from a load or reload register to begin counting again.
Constants
BCM2708_SPI0_*
BCM2708_SPI0_DESCRIPTION = 'BCM2835 SPI0 Master';
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BCM2708_SPI0_MAX_SIZE = $FFFF;
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BCM2708_SPI0_MIN_CLOCK = 3814;
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Default minimum based on the default settings from the firmware (Recalculated during open) |
BCM2708_SPI0_MAX_CLOCK = 125000000;
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Default maximum based on the default settings from the firmware (Recalculated during open) |
BCM2708_SPI0_MIN_DIVIDER = 2;
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Divider is always rounded down to an even number and a value of 0 sets the divider to 65536 |
BCM2708_SPI0_MAX_DIVIDER = $FFFE;
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Divider is always rounded down to an even number |
BCM2708_SPI0_CORE_CLOCK = 250000000;
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Default core clock based on the default settings from the firmware (Requested from firmware during start) |
BCM2708_SPI0_MODE_IRQ = 0;
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BCM2708_SPI0_MODE_DMA = 1;
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BCM2708_BSCI2C_*
BCM2708_BSCI2C_MAX_SIZE = $FFFF;
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BCM2708_BSCI2C_MIN_CLOCK = 3814;
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Default minimum based on the default settings from the firmware (Recalculated during open) |
BCM2708_BSCI2C_MAX_CLOCK = 125000000;
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Default maximum based on the default settings from the firmware (Recalculated during open) |
BCM2708_BSCI2C_DEFAULT_CLOCK = 100000;
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BCM2708_BSCI2C_MIN_DIVIDER = 2;
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Divider is always rounded down to an even number and a value of 0 sets the divider to 32768 |
BCM2708_BSCI2C_MAX_DIVIDER = $FFFE;
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Divider is always rounded down to an even number |
BCM2708_BSCI2C_CORE_CLOCK = 250000000;
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Default core clock based on the default settings from the firmware (Requested from firmware during start) |
BCM2708_BSCI2C_MODE_WRITE = 0;
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BCM2708_BSCI2C_MODE_READ = 1;
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BCM2708_I2C0_*
BCM2708_I2C0_DESCRIPTION = 'BCM2835 BSC0 Master I2C';
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BCM2708_I2C1_*
BCM2708_I2C1_DESCRIPTION = 'BCM2835 BSC1 Master I2C';
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BCM2708_SPI1_*
BCM2708_SPI1_DESCRIPTION = 'BCM2835 AUX SPI1 Master';
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BCM2708_SPI2_*
BCM2708_SPI2_DESCRIPTION = 'BCM2835 AUX SPI2 Master';
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BCM2708_I2CSLAVE_*
BCM2708_I2CSLAVE_DESCRIPTION = 'BCM2835 I2C Slave';
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BCM2708_SPISLAVE_*
BCM2708_SPISLAVE_DESCRIPTION = 'BCM2835 SPI Slave';
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BCM2708_DMA_*
BCM2708_DMA_DESCRIPTION = 'BCM2835 DMA';
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BCM2708_DMA_CHANNEL_COUNT = 16;
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Total number of DMA channels (Not all are usable) |
BCM2708_DMA_LITE_CHANNELS = $7F80;
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Mask of DMA Lite channels (7 to 14) |
BCM2708_DMA_NORMAL_CHANNELS = $007E; {807F}
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Mask of normal channels (1 to 6) |
BCM2708_DMA_BULK_CHANNELS = $8001;
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Mask of DMA Bulk channels (0 and 15) |
BCM2708_DMA_SHARED_CHANNELS = $7800;
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Mask of channels with shared interrupt (11 to 14) |
BCM2708_DMA_MAX_LITE_TRANSFER = 65536;
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Maximum transfer length for a DMA Lite channel |
BCM2708_DMA_MAX_NORMAL_TRANSFER = 1073741824;
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Maximum transfer length for a normal channel |
BCM2708_DMA_MAX_STRIDE = $FFFF;
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Maximum stride value (Increment between rows) (Note this is a signed value (Min -32768 / Max 32767) |
BCM2708_DMA_MAX_Y_COUNT = $3FFF;
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Maximum number of X length transfers in 2D stride |
BCM2708_DMA_MAX_X_LENGTH = $FFFF;
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Maximum X transfer length in 2D stride |
BCM2708_DMA_CB_ALIGNMENT = 32;
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Alignment required for DMA control blocks |
BCM2708_DMA_LITE_BURST_LENGTH = 1;
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Burst length for DMA Lite channels |
BCM2708_DMA_NORMAL_BURST_LENGTH = 2;
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Burst length for normal channels |
BCM2708_DMA_BULK_BURST_LENGTH = 8;
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Burst length for DMA Bulk channels |
BCM2708_PWM_*
BCM2708_PWM_MIN_PERIOD = 108;
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Default based on 19.2MHz PWM clock (Oscillator source) |
BCM2708_PWM_DEFAULT_CLOCK = 19200000;
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Default to the 19.2MHz oscillator clock |
BCM2708_PWM0_*
BCM2708_PWM0_DESCRIPTION = 'BCM2835 PWM0';
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BCM2708_PWM1_*
BCM2708_PWM1_DESCRIPTION = 'BCM2835 PWM1';
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BCM2708_GPIO_*
BCM2708_GPIO_DESCRIPTION = 'BCM2835 GPIO';
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BCM2708_GPIO_MIN_PIN = GPIO_PIN_0;
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BCM2708_GPIO_MAX_PIN = GPIO_PIN_53;
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BCM2708_GPIO_MAX_LEVEL = GPIO_LEVEL_HIGH;
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BCM2708_GPIO_MAX_PULL = GPIO_PULL_DOWN;
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BCM2708_GPIO_MIN_FUNCTION = GPIO_FUNCTION_IN;
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BCM2708_GPIO_MAX_FUNCTION = GPIO_FUNCTION_ALT5;
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BCM2708_GPIO_MIN_TRIGGER = GPIO_TRIGGER_LOW;
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BCM2708_GPIO_MAX_TRIGGER = GPIO_TRIGGER_ASYNC_FALLING;
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GPIO pull up/down to BCM2835 pull up/down | |
BCM2708_GPIO_PULL_MAP:array[GPIO_PULL_NONE..GPIO_PULL_DOWN] of LongWord = (
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BCM2835_GPPUD_NONE,
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BCM2835_GPPUD_UP,
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BCM2835_GPPUD_DOWN);
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GPIO functions to BCM2835 functions | |
BCM2708_GPIO_FUNCTION_MAP:array[BCM2708_GPIO_MIN_FUNCTION..BCM2708_GPIO_MAX_FUNCTION] of LongWord = (
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BCM2835_GPFSEL_IN,
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BCM2835_GPFSEL_OUT,
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BCM2835_GPFSEL_ALT0,
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BCM2835_GPFSEL_ALT1,
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BCM2835_GPFSEL_ALT2,
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BCM2835_GPFSEL_ALT3,
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BCM2835_GPFSEL_ALT4,
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BCM2835_GPFSEL_ALT5);
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BCM2835 functions to GPIO functions | |
BCM2708_GPIO_FUNCTION_UNMAP:array[BCM2708_GPIO_MIN_FUNCTION..BCM2708_GPIO_MAX_FUNCTION] of LongWord = (
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GPIO_FUNCTION_IN,
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GPIO_FUNCTION_OUT,
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GPIO_FUNCTION_ALT5,
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GPIO_FUNCTION_ALT4,
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GPIO_FUNCTION_ALT0,
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GPIO_FUNCTION_ALT1,
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GPIO_FUNCTION_ALT2,
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GPIO_FUNCTION_ALT3);
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GPIO triggers to BCM2835 event registers | |
BCM2708_GPIO_TRIGGER_MAP:array[BCM2708_GPIO_MIN_TRIGGER..BCM2708_GPIO_MAX_TRIGGER] of LongWord = (
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GPIO_FUNCTION_IN,
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BCM2835_GPLEN0,
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BCM2835_GPHEN0,
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BCM2835_GPREN0,
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BCM2835_GPFEN0,
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BCM2835_GPAREN0,
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BCM2835_GPAFEN0);
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BCM2708_UART0_*
BCM2708_UART0_DESCRIPTION = 'BCM2835 PL011 UART';
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BCM2708_UART0_MIN_BAUD = 300;
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Default minimum of 300 baud |
BCM2708_UART0_MAX_BAUD = 187500;
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Default maximum based on the default settings from the firmware (Recalculated during open) |
BCM2708_UART0_MIN_DATABITS = SERIAL_DATA_5BIT;
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BCM2708_UART0_MAX_DATABITS = SERIAL_DATA_8BIT;
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BCM2708_UART0_MIN_STOPBITS = SERIAL_STOP_1BIT;
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BCM2708_UART0_MAX_STOPBITS = SERIAL_STOP_2BIT;
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BCM2708_UART0_MAX_PARITY = SERIAL_PARITY_EVEN;
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BCM2708_UART0_MAX_FLOW = SERIAL_FLOW_RTS_CTS;
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BCM2708_UART0_CLOCK_RATE = 3000000;
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Default clock rate based on the default settings from the firmware (Requested from firmware during open) |
BCM2708_UART1_*
BCM2708_UART1_DESCRIPTION = 'BCM2835 AUX (Mini) UART';
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BCM2708_EMMC_*
BCM2708_EMMC_DESCRIPTION = 'BCM2835 Arasan SD Host';
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BCM2708_EMMC_MIN_FREQ = 400000;
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Default minimum of 400KHz |
BCM2708_EMMC_MAX_FREQ = 250000000;
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BCM2708_SYS_CLOCK_*
BCM2708_SYS_CLOCK_DESCRIPTION = 'BCM2835 System Timer Clock';
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BCM2708_ARM_CLOCK_*
BCM2708_ARM_CLOCK_DESCRIPTION = 'BCM2835 ARM Timer Clock';
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BCM2708_ARM_CLOCK_MIN_RATE = 976562;
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Default minimum (Divider 255) based on the default settings from the firmware (Recalculated during start) |
BCM2708_ARM_CLOCK_MAX_RATE = 250000000;
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Default maximum (Divider 0) based on the default settings from the firmware (Recalculated during start) |
BCM2708_ARM_CLOCK_DEFAULT_RATE = 3968253;
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Default rate (Divider 62) based on the default settings from the firmware (Recalculated during start) |
BCM2708_ARM_CLOCK_MIN_DIVIDER = 0;
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BCM2708_ARM_CLOCK_MAX_DIVIDER = 255;
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BCM2708_ARM_CLOCK_DEFAULT_DIVIDER = 62;
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BCM2708_ARM_CLOCK_CORE_CLOCK = 250000000;
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Default core clock based on the default settings from the firmware (Requested from firmware during start) |
BCM2708_ARM_TIMER_*
BCM2708_ARM_TIMER_DESCRIPTION = 'BCM2835 ARM Timer';
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BCM2708_ARM_TIMER_MIN_RATE = 244140;
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Default minimum (Divider 1023) based on the default settings from the firmware (Recalculated during start) |
BCM2708_ARM_TIMER_MAX_RATE = 250000000;
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Default maximum (Divider 0) based on the default settings from the firmware (Recalculated during start) |
BCM2708_ARM_TIMER_DEFAULT_RATE = 1000000;
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Default rate (Divider 249) based on the default settings from the firmware (Recalculated during start) |
BCM2708_ARM_TIMER_MIN_INTERVAL = 1;
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BCM2708_ARM_TIMER_MAX_INTERVAL = $FFFFFFFF;
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BCM2708_ARM_TIMER_MIN_DIVIDER = 0;
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BCM2708_ARM_TIMER_MAX_DIVIDER = 1023;
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BCM2708_ARM_TIMER_DEFAULT_DIVIDER = 249;
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BCM2708_ARM_TIMER_CORE_CLOCK = 250000000;
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Default core clock based on the default settings from the firmware (Requested from firmware during start) |
BCM2708_RANDOM_*
BCM2708_RANDOM_WARMUP_COUNT = $00040000;
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The initial numbers generated are "less random" so will be discarded |
Type definitions
BCM2708 SPI0 types
PBCM2708SPI0Device = ^TBCM2708SPI0Device;
TBCM2708SPI0Device = record
SPI Properties | |
SPI:TSPIDevice;
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BCM2708 Properties | |
Address:Pointer;
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Device register base address |
CoreClock:LongWord;
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Core clock rate |
Transfer Properties | |
Mode:LongWord;
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Mode of current transfer (BCM2708_SPI0_MODE_IRQ / BCM2708_SPI0_MODE_DMA) |
Source:Pointer;
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Pointer to the source for current transfer (nil if reading only) |
Dest:Pointer;
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Pointer to the destination for current transfer (nil if writing only) |
Count:LongWord;
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Count of bytes for current transfer |
SourceRemain:LongWord;
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Source bytes remaining for current transfer |
DestRemain:LongWord;
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Destination bytes remaining for current transfer |
Statistics Properties | |
InterruptCount:LongWord;
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Number of interrupt requests received by the device |
BCM2708 BSCI2C (I2C0/1) types
PBCM2708BSCI2CDevice = ^TBCM2708BSCI2CDevice;
TBCM2708BSCI2CDevice = record
I2C Properties | |
I2C:TI2CDevice;
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BCM2708 Properties | |
Address:Pointer;
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Device register base address |
CoreClock:LongWord;
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Core clock rate |
SDAPin:LongWord;
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GPIO pin for the SDA line |
SCLPin:LongWord;
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GPIO pin for the SCL line |
SDAFunction:LongWord;
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GPIO function for the SDA line |
SCLFunction:LongWord;
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GPIO function for the SCL line |
Transfer Properties | |
Index:LongWord;
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Index of this device in the IRQData array (Set during device initialization) |
Mode:LongWord;
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Mode of current transfer (BCM2708_BSCI2C_MODE_WRITE / BCM2708_BSCI2C_MODE_READ) |
Data:Pointer;
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Pointer to the data for current transfer |
Count:LongWord;
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Count of bytes for current transfer |
Remain:LongWord;
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Bytes remaining for current transfer |
Statistics Properties | |
InterruptCount:LongWord;
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Number of interrupt requests received by the device |
PBCM2708BSCI2CIRQData = ^TBCM2708BSCI2CIRQData; {BSC I2C devices share a single interrupt}
TBCM2708BSCI2CIRQData = record
Count:LongWord;
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Lock:TSpinHandle;
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Devices:array[0..2] of PBCM2708BSCI2CDevice;
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BCM2708 SPI AUX (SPI1/2) types
PBCM2708SPIAUXDevice = ^TBCM2708SPIAUXDevice;
TBCM2708SPIAUXDevice = record
SPI Properties | |
SPI:TSPIDevice;
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BCM2708 Properties | |
Address:Pointer;
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Device register base address |
CoreClock:LongWord;
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Core clock rate |
BCM2708 DMA types
PBCM2708DMAChannel = ^TBCM2708DMAChannel;
TBCM2708DMAChannel = record
Host:PBCM2708DMAHost;
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DMA host this channel belongs to |
Request:PDMARequest;
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Current DMA request pending on this channel (or nil of no request is pending) |
Number:LongWord;
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The channel number of this channel |
Interrupt:LongWord;
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The interrupt number of this channel |
Registers:PBCM2835DMARegisters;
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The channel registers for configuration |
PBCM2708DMAHost = ^TBCM2708DMAHost;
TBCM2708DMAHost = record
DMA Properties | |
DMA:TDMAHost;
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BCM2708 Properties | |
ChannelMask:LongWord;
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Mask of available channels (Passed from GPU firmware) |
ChannelFree:LongWord;
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Bitmap of current free channels |
ChannelLock:TMutexHandle;
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Lock for access to ChannelFree |
ChannelWait:TSemaphoreHandle;
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Number of free normal channels in ChannelFree |
ChannelLite:TSemaphoreHandle;
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Number of free DMA Lite channels in ChannelFree |
ChannelBulk:TSemaphoreHandle;
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Number of free DMA Bulk channels in ChannelFree |
Channels:array[0..BCM2708_DMA_CHANNEL_COUNT - 1] of TBCM2708DMAChannel;
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Channel information for each DMA channel on the host |
EnableRegister:PLongWord;
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InterruptRegister:PLongWord;
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Statistics Properties | |
InterruptCount:LongWord;
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Number of interrupt requests received by the host controller |
BCM2708 PWM types
PBCM2708PWMDevice = ^TBCM2708PWMDevice;
TBCM2708PWMDevice = record
PWM Properties | |
PWM:TPWMDevice;
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BCM2708 Properties | |
Address:Pointer;
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Device register base address |
Channel:LongWord;
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Channel for this device |
Scaler:LongWord;
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Scaler for Duty cycle and Period |
Pair:PBCM2708PWMDevice;
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The paired PWM device for the other channel |
Audio Properties | |
Audio:PBCM2708PWMAudio;
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The associated PWM Audio device |
PBCM2708PWMAudio = ^TBCM2708PWMAudio;
TBCM2708PWMAudio = record
Audio Properties | |
Audio:TAudioDevice;
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PWM Properties | |
PWM0:PBCM2708PWMDevice;
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The PWM device for channel 0 |
PWM1:PBCM2708PWMDevice;
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The PWM device for channel 1 |
BCM2708 GPIO types
PBCM2708GPIOBank = ^TBCM2708GPIOBank;
TBCM2708GPIOBank = record
GPIO:PGPIODevice;
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Bank:LongWord;
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Address:PtrUInt;
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PinStart:LongWord;
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PBCM2708GPIODevice = ^TBCM2708GPIODevice;
TBCM2708GPIODevice = record
GPIO Properties | |
GPIO:TGPIODevice;
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BCM2708 Properties | |
Lock:TSpinHandle;
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Device lock (Differs from lock in Device portion) (Spin lock due to use by interrupt handler) |
Banks:array[0..BCM2835_GPIO_BANK_COUNT - 1] of TBCM2708GPIOBank;
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Statistics Properties | |
InterruptCount:LongWord;
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Number of interrupt requests received by the device |
BCM2708 UART0 types
PBCM2708UART0Device = ^TBCM2708UART0Device;
TBCM2708UART0Device = record
UART Properties | |
UART:TUARTDevice;
|
|
BCM2708 Properties | |
Address:Pointer;
|
Device register base address |
ClockRate:LongWord;
|
Device clock rate |
Statistics Properties | |
InterruptCount:LongWord;
|
Number of interrupt requests received by the device |
BCM2708 SDHCI types
PBCM2708SDHCIHost = ^TBCM2708SDHCIHost;
TBCM2708SDHCIHost = record
SDHCI Properties | |
SDHCI:TSDHCIHost;
|
|
BCM2708 Properties | |
WriteDelay:LongWord;
|
|
LastWrite:LongWord;
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|
ShadowRegister:LongWord;
|
BCM2708 system clock types
PBCM2708SystemClock = ^TBCM2708SystemClock;
TBCM2708SystemClock = record
Clock Properties | |
Clock:TClockDevice;
|
BCM2708 ARM clock types
PBCM2708ARMClock = ^TBCM2708ARMClock;
TBCM2708ARMClock = record
Clock Properties | |
Clock:TClockDevice;
|
|
BCM2708 Properties | |
CoreClock:LongWord;
|
Core clock rate |
BCM2708 ARM timer types
PBCM2708ARMTimer = ^TBCM2708ARMTimer;
TBCM2708ARMTimer = record
Timer Properties | |
Timer:TTimerDevice;
|
|
BCM2708 Properties | |
CoreClock:LongWord;
|
Core clock rate |
Statistics Properties | |
InterruptCount:LongWord;
|
Number of interrupt requests received by the device |
BCM2708 random types
PBCM2708Random = ^TBCM2708Random;
TBCM2708Random = record
Random Properties | |
Random:TRandomDevice;
|
BCM2708 mailbox types
PBCM2708Mailbox = ^TBCM2708Mailbox;
TBCM2708Mailbox = record
Mailbox Properties | |
Mailbox:TMailboxDevice;
|
BCM2708 watchdog types
PBCM2708Watchdog = ^TBCM2708Watchdog;
TBCM2708Watchdog = record
Watchdog Properties | |
Watchdog:TWatchdogDevice;
|
BCM2708 framebuffer types
PBCM2708Framebuffer = ^TBCM2708Framebuffer;
TBCM2708Framebuffer = record
Framebuffer Properties | |
Framebuffer:TFramebufferDevice;
|
Public variables
None defined
Function declarations
Initialization functions
procedure BCM2708Init;
Note | None documented |
---|
BCM2708 SPI0 functions
function BCM2708SPI0Start(SPI:PSPIDevice;Mode,ClockRate,ClockPhase,ClockPolarity:LongWord):LongWord;
Note | None documented |
---|
function BCM2708SPI0Stop(SPI:PSPIDevice):LongWord;
Note | None documented |
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function BCM2708SPI0WriteRead(SPI:PSPIDevice; ChipSelect:Word; Source,Dest:Pointer; Size,Flags: LongWord; var Count:LongWord):LongWord;
Note | None documented |
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function BCM2708SPI0SetMode(SPI:PSPIDevice; Mode:LongWord):LongWord;
Note | None documented |
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function BCM2708SPI0SetClockRate(SPI:PSPIDevice; ChipSelect:Word; ClockRate:LongWord):LongWord;
Note | None documented |
---|
function BCM2708SPI0SetClockPhase(SPI:PSPIDevice; ClockPhase:LongWord):LongWord;
Note | None documented |
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function BCM2708SPI0SetClockPolarity(SPI:PSPIDevice; ClockPolarity:LongWord):LongWord;
Note | None documented |
---|
function BCM2708SPI0SetSelectPolarity(SPI:PSPIDevice; ChipSelect:Word; SelectPolarity:LongWord):LongWord;
Note | None documented |
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procedure BCM2708SPI0ReadFIFO(SPI:PBCM2708SPI0Device);
Note | Called from within the interrupt handler |
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procedure BCM2708SPI0WriteFIFO(SPI:PBCM2708SPI0Device);
Note | Called from within the interrupt handler |
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procedure BCM2708SPI0InterruptHandler(SPI:PBCM2708SPI0Device);
Note | None documented |
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procedure BCM2708SPI0DMARequestCompleted(Request:PDMARequest);
Note | None documented |
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BCM2708 BSCI2C (I2C0/1) functions
function BCM2708BSCI2CStart(I2C:PI2CDevice; Rate:LongWord):LongWord;
Note | None documented |
---|
function BCM2708BSCI2CStop(I2C:PI2CDevice):LongWord;
Note | None documented |
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function BCM2708BSCI2CRead(I2C:PI2CDevice; Address:Word; Buffer:Pointer; Size:LongWord; var Count:LongWord):LongWord;
Note | None documented |
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function BCM2708BSCI2CWrite(I2C:PI2CDevice; Address:Word; Buffer:Pointer; Size:LongWord; var Count:LongWord):LongWord;
Note | None documented |
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function BCM2708BSCI2CWriteRead(I2C:PI2CDevice; Address:Word; Initial:Pointer; Len:LongWord; Data:Pointer; Size:LongWord; var Count:LongWord):LongWord;
Note | None documented |
---|
function BCM2708BSCI2CWriteWrite(I2C:PI2CDevice; Address:Word; Initial:Pointer; Len:LongWord; Data:Pointer; Size:LongWord; var Count:LongWord):LongWord;
Note | None documented |
---|
function BCM2708BSCI2CSetRate(I2C:PI2CDevice; Rate:LongWord):LongWord;
Note | None documented |
---|
function BCM2708BSCI2CSetAddress(I2C:PI2CDevice; Address:Word):LongWord;
Note | None documented |
---|
procedure BCM2708BSCI2CFillFIFO(I2C:PBCM2708BSCI2CDevice);
Note | Called from within the interrupt handler |
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procedure BCM2708BSCI2CDrainFIFO(I2C:PBCM2708BSCI2CDevice);
Note | Called from within the interrupt handler |
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procedure BCM2708BSCI2CInterruptHandler(IRQData:PBCM2708BSCI2CIRQData);
Note | Thread submitting the current request will hold the I2C device lock |
---|
BCM2708 DMA functions
function BCM2708DMAHostStart(DMA:PDMAHost):LongWord;
Note | None documented |
---|
function BCM2708DMAHostStop(DMA:PDMAHost):LongWord;
Note | None documented |
---|
function BCM2708DMAHostSubmit(DMA:PDMAHost; Request:PDMARequest):LongWord;
Note | None documented |
---|
function BCM2708DMAHostCancel(DMA:PDMAHost; Request:PDMARequest):LongWord;
Note | None documented |
---|
procedure BCM2708DMAInterruptHandler(Channel:PBCM2708DMAChannel);
Note | None documented |
---|
procedure BCM2708DMASharedInterruptHandler(DMA:PBCM2708DMAHost);
Note | None documented |
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procedure BCM2708DMARequestComplete(Channel:PBCM2708DMAChannel);
Note | None documented |
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function BCM2708DMAPeripheralToDREQ(Peripheral:LongWord):LongWord;
Note | None documented |
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procedure BCM2708DMADataToControlBlock(Request:PDMARequest; Data:PDMAData; Block:PBCM2835DMAControlBlock; Bulk,Lite:Boolean);
Note | None documented |
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BCM2708 PWM0/1 functions
function BCM2708PWMStart(PWM:PPWMDevice):LongWord;
Note | None documented |
---|
function BCM2708PWMStop(PWM:PPWMDevice):LongWord;
Note | None documented |
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function BCM2708PWMWrite(PWM:PPWMDevice; Value:LongWord):LongWord;
Note | None documented |
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function BCM2708PWMSetGPIO(PWM:PPWMDevice; GPIO:LongWord):LongWord;
Note | None documented |
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function BCM2708PWMResetGPIO(PWM:PPWMDevice; GPIO:LongWord):LongWord;
Note | None documented |
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function BCM2708PWMSetMode(PWM:PPWMDevice; Mode:LongWord):LongWord;
Note | None documented |
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function BCM2708PWMSetRange(PWM:PPWMDevice; Range:LongWord):LongWord;
Note | None documented |
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function BCM2708PWMSetFrequency(PWM:PPWMDevice; Frequency:LongWord):LongWord;
Note | None documented |
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function BCM2708PWMSetPolarity(PWM:PPWMDevice; Polarity:LongWord):LongWord;
Note | None documented |
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function BCM2708PWMConfigure(PWM:PPWMDevice; DutyNS,PeriodNS:LongWord):LongWord;
Note | None documented |
---|
function BCM2708PWMClockStart(PWM:PPWMDevice; Frequency:LongWord):LongWord;
Note | None documented |
---|
function BCM2708PWMClockStop(PWM:PPWMDevice):LongWord;
Note | None documented |
---|
function BCM2708PWMClockEnabled(PWM:PPWMDevice):Boolean;
Note | None documented |
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BCM2708 GPIO functions
function BCM2708GPIOStart(GPIO:PGPIODevice):LongWord;
Note | None documented |
---|
function BCM2708GPIOStop(GPIO:PGPIODevice):LongWord;
Note | None documented |
---|
function BCM2708GPIORead(GPIO:PGPIODevice;Reg:LongWord):LongWord;
Note | None documented |
---|
procedure BCM2708GPIOWrite(GPIO:PGPIODevice; Reg,Value:LongWord);
Note | None documented |
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function BCM2708GPIOInputGet(GPIO:PGPIODevice; Pin:LongWord):LongWord;
Note | None documented |
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function BCM2708GPIOInputWait(GPIO:PGPIODevice; Pin,Trigger,Timeout:LongWord):LongWord;
Note | None documented |
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function BCM2708GPIOInputEvent(GPIO:PGPIODevice; Pin,Trigger,Flags,Timeout:LongWord; Callback:TGPIOCallback; Data:Pointer):LongWord;
Note | None documented |
---|
function BCM2708GPIOInputCancel(GPIO:PGPIODevice; Pin:LongWord):LongWord;
Note | None documented |
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function BCM2708GPIOOutputSet(GPIO:PGPIODevice; Pin,Level:LongWord):LongWord;
Note | None documented |
---|
function BCM2708GPIOPullSelect(GPIO:PGPIODevice; Pin,Mode:LongWord):LongWord;
Note | None documented |
---|
function BCM2708GPIOFunctionGet(GPIO:PGPIODevice; Pin:LongWord):LongWord;
Note | None documented |
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function BCM2708GPIOFunctionSelect(GPIO:PGPIODevice; Pin,Mode:LongWord):LongWord;
Note | None documented |
---|
procedure BCM2708GPIOInterruptHandler(Bank:PBCM2708GPIOBank);
Note | None documented |
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procedure BCM2708GPIOEventTrigger(Pin:PGPIOPin);
Note | None documented |
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procedure BCM2708GPIOEventTimeout(Event:PGPIOEvent);
Note | None documented |
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BCM2708 UART0 functions
function BCM2708UART0Open(UART:PUARTDevice; BaudRate,DataBits,StopBits,Parity,FlowControl:LongWord):LongWord;
Note | None documented |
---|
function BCM2708UART0Close(UART:PUARTDevice):LongWord;
Note | None documented |
---|
function BCM2708UART0Read(UART:PUARTDevice; Buffer:Pointer; Size,Flags:LongWord; var Count:LongWord):LongWord;
Note | None documented |
---|
function BCM2708UART0Write(UART:PUARTDevice; Buffer:Pointer; Size,Flags:LongWord; var Count:LongWord):LongWord;
Note | None documented |
---|
function BCM2708UART0Status(UART:PUARTDevice):LongWord;
Note | None documented |
---|
procedure BCM2708UART0InterruptHandler(UART:PUARTDevice);
Note | None documented |
---|
procedure BCM2708UART0Receive(UART:PUARTDevice);
Note | None documented |
---|
procedure BCM2708UART0Transmit(UART:PUARTDevice);
Note | None documented |
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BCM2708 SDHCI functions
function BCM2708SDHCIHostStart(SDHCI:PSDHCIHost):LongWord;
Note | None documented |
---|
function BCM2708SDHCIHostStop(SDHCI:PSDHCIHost):LongWord;
Note | None documented |
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function BCM2708SDHCIHostReadByte(SDHCI:PSDHCIHost; Reg:LongWord):Byte;
Note | The Broadcom document BCM2835-ARM-Peripherals page 66 states the following: Contrary to Arasans documentation the EMMC module registers can only be accessed as 32 bit registers, i.e. the two LSBs of the address are always zero. For this reason this code must simulate Byte and Word reads using LongWord reads. |
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function BCM2708SDHCIHostReadWord(SDHCI:PSDHCIHost; Reg:LongWord):Word;
Note | The Broadcom document BCM2835-ARM-Peripherals page 66 states the following: Contrary to Arasans documentation the EMMC module registers can only be accessed as 32 bit registers, i.e. the two LSBs of the address are always zero. For this reason this code must simulate Byte and Word reads using LongWord reads. |
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function BCM2708SDHCIHostReadLong(SDHCI:PSDHCIHost; Reg:LongWord):LongWord;
Note | None documented |
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procedure BCM2708SDHCIHostWriteByte(SDHCI:PSDHCIHost; Reg:LongWord; Value:Byte);
Note | The Broadcom document BCM2835-ARM-Peripherals page 66 states the following: Contrary to Arasans documentation the EMMC module registers can only be accessed as 32 bit registers, i.e. the two LSBs of the address are always zero. For this reason this code must simulate Byte and Word writes using LongWord writes. |
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procedure BCM2708SDHCIHostWriteWord(SDHCI:PSDHCIHost; Reg:LongWord; Value:Word);
Note | The Broadcom document BCM2835-ARM-Peripherals page 66 states the following: Contrary to Arasans documentation the EMMC module registers can only be accessed as 32 bit registers, i.e. the two LSBs of the address are always zero. For this reason this code must simulate Byte and Word writes using LongWord writes. |
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procedure BCM2708SDHCIHostWriteLong(SDHCI:PSDHCIHost; Reg:LongWord; Value:LongWord);
Note | The source code of U-Boot and Linux kernel drivers have this comment The Arasan has a bugette whereby it may lose the content of successive writes to registers that are within two SD-card clock cycles of each other (a clock domain crossing problem). It seems, however, that the data register does not have this problem. (Which is just as well - otherwise we'd have to nobble the DMA engine too) For this reason this code must delay after each write to the registers. |
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procedure BCM2708SDHCIInterruptHandler(SDHCI:PSDHCIHost);
Note | None documented |
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function BCM2708SDHCISetupInterrupts(SDHCI:PSDHCIHost):LongWord;
Note | None documented |
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function BCM2708MMCDeviceGetCardDetect(MMC:PMMCDevice):LongWord;
Note | None documented |
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BCM2708 system clock functions
function BCM2708SystemClockRead(Clock:PClockDevice):LongWord;
Note | Not intended to be called directly by applications, use ClockDeviceRead instead. |
---|
function BCM2708SystemClockRead64(Clock:PClockDevice):Int64;
Note | Not intended to be called directly by applications, use ClockDeviceRead64 instead. |
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BCM2708 ARM clock functions
function BCM2708ARMClockStart(Clock:PClockDevice):LongWord;
Note | Not intended to be called directly by applications, use ClockDeviceStart instead. |
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function BCM2708ARMClockStop(Clock:PClockDevice):LongWord;
Note | Not intended to be called directly by applications, use ClockDeviceStop instead. |
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function BCM2708ARMClockRead(Clock:PClockDevice):LongWord;
Note | Not intended to be called directly by applications, use ClockDeviceRead instead. |
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function BCM2708ARMClockRead64(Clock:PClockDevice):Int64;
Note | Not intended to be called directly by applications, use ClockDeviceRead64 instead. |
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function BCM2708ARMClockSetRate(Clock:PClockDevice; Rate:LongWord):LongWord;
Note | Not intended to be called directly by applications, use ClockDeviceSetRate instead. |
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BCM2708 ARM timer functions
function BCM2708ARMTimerStart(Timer:PTimerDevice):LongWord;
Note | Not intended to be called directly by applications, use TimerDeviceStart instead |
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function BCM2708ARMTimerStop(Timer:PTimerDevice):LongWord;
Note | Not intended to be called directly by applications, use TimerDeviceStop instead |
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function BCM2708ARMTimerRead64(Timer:PTimerDevice):Int64;
Note | Not intended to be called directly by applications, use TimerDeviceRead64 instead |
---|
function BCM2708ARMTimerWait(Timer:PTimerDevice):LongWord;
Note | Not intended to be called directly by applications, use TimerDeviceWait instead |
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function BCM2708ARMTimerEvent(Timer:PTimerDevice; Flags:LongWord; Callback:TTimerCallback; Data:Pointer):LongWord;
Note | Not intended to be called directly by applications, use TimerDeviceEvent instead |
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function BCM2708ARMTimerCancel(Timer:PTimerDevice):LongWord;
Note | Not intended to be called directly by applications, use TimerDeviceCancel instead |
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function BCM2708ARMTimerSetRate(Timer:PTimerDevice; Rate:LongWord):LongWord;
Note | Not intended to be called directly by applications, use TimerDeviceSetRate instead |
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function BCM2708ARMTimerSetInterval(Timer:PTimerDevice; Interval:LongWord):LongWord;
Note | Not intended to be called directly by applications, use TimerDeviceSetInterval instead |
---|
procedure BCM2708ARMTimerInterruptHandler(Timer:PTimerDevice);
Note | Not intended to be called directly by applications |
---|
procedure BCM2708ARMTimerEventTrigger(Timer:PTimerDevice);
Note | Not intended to be called directly by applications |
---|
BCM2708 random functions
function BCM2708RandomStart(Random:PRandomDevice):LongWord;
Note | None documented |
---|
function BCM2708RandomStop(Random:PRandomDevice):LongWord;
Note | None documented |
---|
function BCM2708RandomReadLongWord(Random:PRandomDevice):LongWord;
Note | None documented |
---|
BCM2708 watchdog functions
function BCM2708WatchdogStart(Watchdog:PWatchdogDevice):LongWord;
Note | None documented |
---|
function BCM2708WatchdogStop(Watchdog:PWatchdogDevice):LongWord;
Note | None documented |
---|
function BCM2708WatchdogRefresh(Watchdog:PWatchdogDevice):LongWord;
Note | None documented |
---|
function BCM2708WatchdogGetRemain(Watchdog:PWatchdogDevice):LongWord;
Note | None documented |
---|
BCM2708 framebuffer functions
function BCM2708FramebufferAllocate(Framebuffer:PFramebufferDevice; Properties:PFramebufferProperties):LongWord;
Note | Not intended to be called directly by applications, use FramebufferDeviceAllocate instead. |
---|
function BCM2708FramebufferRelease(Framebuffer:PFramebufferDevice):LongWord;
Note | Not intended to be called directly by applications, use FramebufferDeviceRelease instead. |
---|
function BCM2708FramebufferBlank(Framebuffer:PFramebufferDevice; Blank:Boolean):LongWord;
Note | Not intended to be called directly by applications, use FramebufferDeviceBlank instead. |
---|
function BCM2708FramebufferCommit(Framebuffer:PFramebufferDevice; Address,Size,Flags:LongWord):LongWord;
Note | Not intended to be called directly by applications, use FramebufferDeviceCommit instead. |
---|
function BCM2708FramebufferWaitSync(Framebuffer:PFramebufferDevice):LongWord;
Note | Not intended to be called directly by applications, use FramebufferDeviceWaitSync instead. |
---|
function BCM2708FramebufferSetOffset(Framebuffer:PFramebufferDevice; X,Y:LongWord; Pan:Boolean):LongWord;
Note | Not intended to be called directly by applications, use FramebufferDeviceSetOffset instead. |
---|
function BCM2708FramebufferGetPalette(Framebuffer:PFramebufferDevice; Palette:PFramebufferPalette):LongWord;
Note | Not intended to be called directly by applications, use FramebufferDeviceGetPalette instead. |
---|
function BCM2708FramebufferSetPalette(Framebuffer:PFramebufferDevice; Palette:PFramebufferPalette):LongWord;
Note | Not intended to be called directly by applications, use FramebufferDeviceSetPalette instead. |
---|
function BCM2708FramebufferSetBacklight(Framebuffer:PFramebufferDevice; Brightness:LongWord):LongWord;
Note | Not intended to be called directly by applications, use FramebufferDeviceSetBacklight instead. |
---|
function BCM2708FramebufferSetProperties(Framebuffer:PFramebufferDevice; Properties:PFramebufferProperties):LongWord;
Note | Not intended to be called directly by applications, use FramebufferDeviceSetProperties instead. |
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