Unit UART

From Ultibo.org
Revision as of 02:21, 5 January 2017 by Ultibo (Talk | contribs)

Jump to: navigation, search

Return to Unit Reference


Description


Ultibo UART interface unit

UART (Universal Asynchronous Receiver Transmitter) devices represent the industry standard serial communications devices that are available on almost every system.

This unit implements the framework for UART devices and provides a standardized API to allow driver specific implementation to be abstracted. All UART devices are also represented as a serial device and this unit handles the relationship between the two devices.

Each UART device returns a set of properties that describe the capabilities of the device and includes a set of flags that indicate what features are supported.

Reads and writes to UART devices are unbuffered and simply pass raw data to and from the caller unless the serial interface is used instead which includes buffering of transmitted and received data. Both reads and writes allow for non blocking so that a caller can avoid waiting for received data to be available or the device to be ready to transmit.

Constants



UART specific constants UART_*
UART_NAME_PREFIX = 'UART'; Name prefix for UART Devices


UART device type constants UART_TYPE_*
UART_TYPE_NONE = 0;  
UART_TYPE_8250 = 1; 8250 UART and similar variants (Differences are handled by driver)
UART_TYPE_16550 = 2; 16550 UART and similar variants (eg 16550A) (Differences are handled by driver)
UART_TYPE_16650 = 3; 16650 UART and similar variants (eg 16C650) (Differences are handled by driver)


UART device mode constants UART_MODE_*
UART_MODE_NONE = 0;  
UART_MODE_UART = 1; The UART was opened as a UART device and all reads and writes are direct
UART_MODE_SERIAL = 2; The UART was opened as a Serial device so reads and writes are being buffered


UART device state constants UART_STATE_*
UART_STATE_DISABLED = 0;  
UART_STATE_ENABLED = 1;  


UART device flag constants UART_FLAG_*
UART_FLAG_NONE = SERIAL_FLAG_NONE;  
UART_FLAG_DATA_8BIT = SERIAL_FLAG_DATA_8BIT; Device supports 8 data bits
UART_FLAG_DATA_7BIT = SERIAL_FLAG_DATA_7BIT; Device supports 7 data bits
UART_FLAG_DATA_6BIT = SERIAL_FLAG_DATA_6BIT; Device supports 6 data bits
UART_FLAG_DATA_5BIT = SERIAL_FLAG_DATA_5BIT; Device supports 5 data bits
UART_FLAG_STOP_1BIT = SERIAL_FLAG_STOP_1BIT; Device supports 1 stop bit
UART_FLAG_STOP_2BIT = SERIAL_FLAG_STOP_2BIT; Device supports 2 stop bits
UART_FLAG_STOP_1BIT5 = SERIAL_FLAG_STOP_1BIT5; Device supports 1.5 stop bits
UART_FLAG_PARITY_ODD = SERIAL_FLAG_PARITY_ODD; Device supports odd parity
UART_FLAG_PARITY_EVEN = SERIAL_FLAG_PARITY_EVEN; Device supports even parity
UART_FLAG_PARITY_MARK = SERIAL_FLAG_PARITY_MARK; Device supports mark parity
UART_FLAG_PARITY_SPACE = SERIAL_FLAG_PARITY_SPACE; Device supports space parity
UART_FLAG_FLOW_RTS_CTS = SERIAL_FLAG_FLOW_RTS_CTS; Device supports RTS/CTS flow control
UART_FLAG_FLOW_DSR_DTR = SERIAL_FLAG_FLOW_DSR_DTR; Device supports DSR/DTR flow control


UART read flag constants UART_READ_*
UART_READ_NONE = SERIAL_READ_NONE;  
UART_READ_NON_BLOCK = SERIAL_READ_NON_BLOCK; Do not block when receiving, if the FIFO is empty return immediately


UART write flag constants UART_WRITE_*
UART_WRITE_NONE = SERIAL_WRITE_NONE;  
UART_WRITE_NON_BLOCK = SERIAL_WRITE_NON_BLOCK; Do not block when transmitting, if the FIFO is full return immediately


UART status flag constants UART_STATUS_*
UART_STATUS_NONE = SERIAL_STATUS_NONE;  
UART_STATUS_RTS = SERIAL_STATUS_RTS;  
UART_STATUS_CTS = SERIAL_STATUS_CTS;  
UART_STATUS_DSR = SERIAL_STATUS_DSR;  
UART_STATUS_DTR = SERIAL_STATUS_DTR;  
UART_STATUS_RX_FULL = SERIAL_STATUS_RX_FULL;  
UART_STATUS_RX_EMPTY = SERIAL_STATUS_RX_EMPTY;  
UART_STATUS_TX_FULL = SERIAL_STATUS_TX_FULL;  
UART_STATUS_TX_EMPTY = SERIAL_STATUS_TX_EMPTY;  
UART_STATUS_BUSY = SERIAL_STATUS_BUSY;  
UART_STATUS_BREAK_ERROR = SERIAL_STATUS_BREAK_ERROR;  
UART_STATUS_PARITY_ERROR = SERIAL_STATUS_PARITY_ERROR;  
UART_STATUS_FRAMING_ERROR = SERIAL_STATUS_FRAMING_ERROR;  
UART_STATUS_OVERRUN_ERROR = SERIAL_STATUS_OVERRUN_ERROR;  
UART_STATUS_DCD = SERIAL_STATUS_DCD;  
UART_STATUS_RI = SERIAL_STATUS_RI;  


UART logging constants UART_LOG_*
UART_LOG_LEVEL_DEBUG = LOG_LEVEL_DEBUG; UART debugging messages
UART_LOG_LEVEL_INFO = LOG_LEVEL_INFO; UART informational messages, such as a device being attached or detached
UART_LOG_LEVEL_ERROR = LOG_LEVEL_ERROR; UART error messages
UART_LOG_LEVEL_NONE = LOG_LEVEL_NONE; No UART messages


Type definitions


To be documented

Public variables



UART logging

UART_DEFAULT_LOG_LEVEL:LongWord = UART_LOG_LEVEL_DEBUG; Minimum level for UART messages. Only messages with level greater than or equal to this will be printed.
UART_LOG_ENABLED:Boolean;


Function declarations



Initialization functions

procedure UARTInit;
Description: Initialize the UART unit and UART device table
Note Called only during system startup


UART functions

function UARTDeviceOpen(UART:PUARTDevice; BaudRate,DataBits,StopBits,Parity,FlowControl:LongWord):LongWord;
Description: To be documented
Note None documented


function UARTDeviceClose(UART:PUARTDevice):LongWord;
Description: To be documented
Note None documented


function UARTDeviceRead(UART:PUARTDevice; Buffer:Pointer; Size,Flags:LongWord;var Count:LongWord):LongWord;
Description: To be documented
Note None documented


function UARTDeviceWrite(UART:PUARTDevice; Buffer:Pointer; Size,Flags:LongWord;var Count:LongWord):LongWord;
Description: To be documented
Note None documented


function UARTDeviceStatus(UART:PUARTDevice):LongWord;
Description: To be documented
Note None documented


function UARTDeviceProperties(UART:PUARTDevice; Properties:PUARTProperties):LongWord;
Description: To be documented
Note None documented


function UARTDeviceCreate:PUARTDevice;
Description: Create a new UART entry
Return Pointer to new UART entry or nil if UART could not be created


function UARTDeviceCreateEx(Size:LongWord):PUARTDevice;
Description: Create a new UART entry
Size Size in bytes to allocate for new UART (Including the UART entry)
Return Pointer to new UART entry or nil if UART could not be created


function UARTDeviceDestroy(UART:PUARTDevice):LongWord;
Description: Destroy an existing UART entry
Note None documented


function UARTDeviceRegister(UART:PUARTDevice):LongWord;
Description: Register a new UART in the UART table
Note None documented


function UARTDeviceDeregister(UART:PUARTDevice):LongWord;
Description: Deregister a UART from the UART table
Note None documented


function UARTDeviceFind(UARTId:LongWord):PUARTDevice;
Description: To be documented
Note None documented


function UARTDeviceFindByName(const Name:String):PUARTDevice; inline;
Description: To be documented
Note None documented


function UARTDeviceFindByDescription(const Description:String):PUARTDevice; inline;
Description: To be documented
Note None documented


function UARTDeviceEnumerate(Callback:TUARTEnumerate; Data:Pointer):LongWord;
Description: To be documented
Note None documented


function UARTDeviceNotification(UART:PUARTDevice; Callback:TUARTNotification; Data:Pointer; Notification,Flags:LongWord):LongWord;
Description: To be documented
Note None documented


UART serial functions

function UARTSerialDeviceOpen(Serial:PSerialDevice; BaudRate,DataBits,StopBits,Parity,FlowControl,ReceiveDepth,TransmitDepth:LongWord):LongWord;
Description: To be documented
Note None documented


function UARTSerialDeviceClose(Serial:PSerialDevice):LongWord;
Description: To be documented
Note None documented


function UARTSerialDeviceRead(Serial:PSerialDevice; Buffer:Pointer; Size,Flags:LongWord; var Count:LongWord):LongWord;
Description: To be documented
Note None documented


function UARTSerialDeviceWrite(Serial:PSerialDevice; Buffer:Pointer; Size,Flags:LongWord; var Count:LongWord):LongWord;
Description: To be documented
Note None documented


function UARTSerialDeviceStatus(Serial:PSerialDevice):LongWord;
Description: To be documented
Note None documented


function UARTSerialDeviceProperties(Serial:PSerialDevice; Properties:PSerialProperties):LongWord;
Description: To be documented
Note None documented


UART helper functions

function UARTGetCount:LongWord; inline;
Description: Get the current UART count
Note None documented


function UARTDeviceGetDefault:PUARTDevice; inline;
Description: Get the current default UART device
Note None documented


function UARTDeviceSetDefault(UART:PUARTDevice):LongWord;
Description: Set the current default UART device
Note None documented


function UARTDeviceCheck(UART:PUARTDevice):PUARTDevice;
Description: Check if the supplied UART is in the UART table
Note None documented


procedure UARTLog(Level:LongWord;UART:PUARTDevice; const AText:String);
Description: To be documented
Note None documented


procedure UARTLogInfo(UART:PUARTDevice; const AText:String); inline;
Description: To be documented
Note None documented


procedure UARTLogError(UART:PUARTDevice; const AText:String); inline;
Description: To be documented
Note None documented


procedure UARTLogDebug(UART:PUARTDevice; const AText:String); inline;
Description: To be documented
Note None documented


UART serial helper functions

function UARTSerialDeviceReceive(UART:PUARTDevice):LongWord;
Description: To be documented
Note None documented


function UARTSerialDeviceTransmit(UART:PUARTDevice):LongWord;
Description: To be documented
Note None documented


Return to Unit Reference