Difference between revisions of "Unit I2C"

From Ultibo.org
Jump to: navigation, search
Line 717: Line 717:
 
{| class="wikitable" style="font-size: 14px; background: white;"
 
{| class="wikitable" style="font-size: 14px; background: white;"
 
|-
 
|-
−
! Note
+
! I2C
−
| None documented
+
| The I2C device to destroy
 +
|-
 +
! Return
 +
| ERROR_SUCCESS if completed or another error code on failure
 
|-
 
|-
 
|}
 
|}
Line 729: Line 732:
 
{| class="wikitable" style="font-size: 14px; background: white;"
 
{| class="wikitable" style="font-size: 14px; background: white;"
 
|-
 
|-
−
! Note
+
! I2C
−
| None documented
+
| The I2C device to register
 +
|-
 +
! Return
 +
| ERROR_SUCCESS if completed or another error code on failure
 
|-
 
|-
 
|}
 
|}
Line 737: Line 743:
 
<div class="toccolours mw-collapsible mw-collapsed" style="border: 1; font-family: arial; padding-top: 0px; padding-bottom: 15px;">
 
<div class="toccolours mw-collapsible mw-collapsed" style="border: 1; font-family: arial; padding-top: 0px; padding-bottom: 15px;">
 
<pre style="border: 0; padding-bottom:0px;">function I2CDeviceDeregister(I2C:PI2CDevice):LongWord;</pre>
 
<pre style="border: 0; padding-bottom:0px;">function I2CDeviceDeregister(I2C:PI2CDevice):LongWord;</pre>
−
<div style="font-size: 14px; padding-left: 12px;">'''Description:''' Deregister a I2C from the I2C table</div>
+
<div style="font-size: 14px; padding-left: 12px;">'''Description:''' Deregister an I2C from the I2C table</div>
 
<div class="mw-collapsible-content" style="text-align: left; padding-left: 5px;">
 
<div class="mw-collapsible-content" style="text-align: left; padding-left: 5px;">
 
{| class="wikitable" style="font-size: 14px; background: white;"
 
{| class="wikitable" style="font-size: 14px; background: white;"
 
|-
 
|-
−
! Note
+
! I2C
−
| None documented
+
| The I2C device to deregister
 +
|-
 +
! Return
 +
| ERROR_SUCCESS if completed or another error code on failure
 
|-
 
|-
 
|}
 
|}
Line 749: Line 758:
 
<div class="toccolours mw-collapsible mw-collapsed" style="border: 1; font-family: arial; padding-top: 0px; padding-bottom: 15px;">
 
<div class="toccolours mw-collapsible mw-collapsed" style="border: 1; font-family: arial; padding-top: 0px; padding-bottom: 15px;">
 
<pre style="border: 0; padding-bottom:0px;">function I2CDeviceFind(I2CId:LongWord):PI2CDevice;</pre>
 
<pre style="border: 0; padding-bottom:0px;">function I2CDeviceFind(I2CId:LongWord):PI2CDevice;</pre>
−
<div style="font-size: 14px; padding-left: 12px;">'''Description:''' To be documented</div>
+
<div style="font-size: 14px; padding-left: 12px;">'''Description:''' Find an I2C device by ID in the I2C table</div>
 
<div class="mw-collapsible-content" style="text-align: left; padding-left: 5px;">
 
<div class="mw-collapsible-content" style="text-align: left; padding-left: 5px;">
 
{| class="wikitable" style="font-size: 14px; background: white;"
 
{| class="wikitable" style="font-size: 14px; background: white;"
 
|-
 
|-
−
! Note
+
! I2CId
−
| None documented
+
| The ID number of the I2C device to find
 +
|-
 +
! Return
 +
| Pointer to I2C device entry or nil if not found
 
|-
 
|-
 
|}
 
|}
Line 761: Line 773:
 
<div class="toccolours mw-collapsible mw-collapsed" style="border: 1; font-family: arial; padding-top: 0px; padding-bottom: 15px;">
 
<div class="toccolours mw-collapsible mw-collapsed" style="border: 1; font-family: arial; padding-top: 0px; padding-bottom: 15px;">
 
<pre style="border: 0; padding-bottom:0px;">function I2CDeviceFindByName(const Name:String):PI2CDevice; inline;</pre>
 
<pre style="border: 0; padding-bottom:0px;">function I2CDeviceFindByName(const Name:String):PI2CDevice; inline;</pre>
−
<div style="font-size: 14px; padding-left: 12px;">'''Description:''' To be documented</div>
+
<div style="font-size: 14px; padding-left: 12px;">'''Description:''' Find an I2C device by name in the device table</div>
 
<div class="mw-collapsible-content" style="text-align: left; padding-left: 5px;">
 
<div class="mw-collapsible-content" style="text-align: left; padding-left: 5px;">
 
{| class="wikitable" style="font-size: 14px; background: white;"
 
{| class="wikitable" style="font-size: 14px; background: white;"
 
|-
 
|-
−
! Note
+
! Name
−
| None documented
+
| The name of the I2C device to find (eg I2C0)
 +
|-
 +
! Return
 +
| Pointer to I2C device entry or nil if not found
 
|-
 
|-
 
|}
 
|}
Line 773: Line 788:
 
<div class="toccolours mw-collapsible mw-collapsed" style="border: 1; font-family: arial; padding-top: 0px; padding-bottom: 15px;">
 
<div class="toccolours mw-collapsible mw-collapsed" style="border: 1; font-family: arial; padding-top: 0px; padding-bottom: 15px;">
 
<pre style="border: 0; padding-bottom:0px;">function I2CDeviceFindByDescription(const Description:String):PI2CDevice; inline;</pre>
 
<pre style="border: 0; padding-bottom:0px;">function I2CDeviceFindByDescription(const Description:String):PI2CDevice; inline;</pre>
−
<div style="font-size: 14px; padding-left: 12px;">'''Description:''' To be documented</div>
+
<div style="font-size: 14px; padding-left: 12px;">'''Description:''' Find an I2C device by description in the device table</div>
 
<div class="mw-collapsible-content" style="text-align: left; padding-left: 5px;">
 
<div class="mw-collapsible-content" style="text-align: left; padding-left: 5px;">
 
{| class="wikitable" style="font-size: 14px; background: white;"
 
{| class="wikitable" style="font-size: 14px; background: white;"
 
|-
 
|-
−
! Note
+
! Description
−
| None documented
+
| The description of the I2C to find (eg BCM2837 BSC1 Master I2C)
 +
|-
 +
! Return
 +
| Pointer to I2C device entry or nil if not found
 
|-
 
|-
 
|}
 
|}
Line 785: Line 803:
 
<div class="toccolours mw-collapsible mw-collapsed" style="border: 1; font-family: arial; padding-top: 0px; padding-bottom: 15px;">
 
<div class="toccolours mw-collapsible mw-collapsed" style="border: 1; font-family: arial; padding-top: 0px; padding-bottom: 15px;">
 
<pre style="border: 0; padding-bottom:0px;">function I2CDeviceEnumerate(Callback:TI2CEnumerate; Data:Pointer):LongWord;</pre>
 
<pre style="border: 0; padding-bottom:0px;">function I2CDeviceEnumerate(Callback:TI2CEnumerate; Data:Pointer):LongWord;</pre>
−
<div style="font-size: 14px; padding-left: 12px;">'''Description:''' To be documented</div>
+
<div style="font-size: 14px; padding-left: 12px;">'''Description:''' Enumerate all I2C devices in the I2C table</div>
 
<div class="mw-collapsible-content" style="text-align: left; padding-left: 5px;">
 
<div class="mw-collapsible-content" style="text-align: left; padding-left: 5px;">
 
{| class="wikitable" style="font-size: 14px; background: white;"
 
{| class="wikitable" style="font-size: 14px; background: white;"
 
|-
 
|-
−
! Note
+
! Callback
−
| None documented
+
| The callback function to call for each I2C device in the table
 +
|-
 +
! Data
 +
| A private data pointer to pass to callback for each I2C device in the table
 +
|-
 +
! Return
 +
| ERROR_SUCCESS if completed or another error code on failure
 
|-
 
|-
 
|}
 
|}
Line 797: Line 821:
 
<div class="toccolours mw-collapsible mw-collapsed" style="border: 1; font-family: arial; padding-top: 0px; padding-bottom: 15px;">
 
<div class="toccolours mw-collapsible mw-collapsed" style="border: 1; font-family: arial; padding-top: 0px; padding-bottom: 15px;">
 
<pre style="border: 0; padding-bottom:0px;">function I2CDeviceNotification(I2C:PI2CDevice; Callback:TI2CNotification; Data:Pointer; Notification,Flags:LongWord):LongWord;</pre>
 
<pre style="border: 0; padding-bottom:0px;">function I2CDeviceNotification(I2C:PI2CDevice; Callback:TI2CNotification; Data:Pointer; Notification,Flags:LongWord):LongWord;</pre>
−
<div style="font-size: 14px; padding-left: 12px;">'''Description:''' To be documented</div>
+
<div style="font-size: 14px; padding-left: 12px;">'''Description:''' Register a notification for I2C device changes</div>
 
<div class="mw-collapsible-content" style="text-align: left; padding-left: 5px;">
 
<div class="mw-collapsible-content" style="text-align: left; padding-left: 5px;">
 
{| class="wikitable" style="font-size: 14px; background: white;"
 
{| class="wikitable" style="font-size: 14px; background: white;"
 
|-
 
|-
−
! Note
+
! Device
−
| None documented
+
| The I2C device to notify changes for (Optional, pass nil for all I2C devices)
 +
|-
 +
! Callback
 +
| The function to call when a notification event occurs
 +
|-
 +
! Data
 +
| A private data pointer to pass to callback when a notification event occurs
 +
|-
 +
! Notification
 +
| The events to register for notification of (eg DEVICE_NOTIFICATION_REGISTER)
 +
|-
 +
! Flags
 +
| The flags to control the notification (eg NOTIFIER_FLAG_WORKER)
 +
|-
 +
|}
 +
</div></div>
 +
<br />
 +
 
 +
'''I2C slave functions'''
 +
 
 +
<div class="toccolours mw-collapsible mw-collapsed" style="border: 1; font-family: arial; padding-top: 0px; padding-bottom: 15px;">
 +
<pre style="border: 0; padding-bottom:0px;">function I2CSlaveStart(I2C:PI2CDevice):LongWord; inline;</pre>
 +
<div style="font-size: 14px; padding-left: 12px;">'''Description:''' Start the specified I2C slave ready for reading and writing</div>
 +
<div class="mw-collapsible-content" style="text-align: left; padding-left: 5px;">
 +
{| class="wikitable" style="font-size: 14px; background: white;"
 +
|-
 +
! I2C
 +
| The I2C slave to start
 +
|-
 +
! Return
 +
| ERROR_SUCCESS if completed or another error code on failure
 +
|-
 +
|}
 +
</div></div>
 +
<br />
 +
<div class="toccolours mw-collapsible mw-collapsed" style="border: 1; font-family: arial; padding-top: 0px; padding-bottom: 15px;">
 +
<pre style="border: 0; padding-bottom:0px;">function I2CSlaveStop(I2C:PI2CDevice):LongWord; inline;</pre>
 +
<div style="font-size: 14px; padding-left: 12px;">'''Description:''' Stop the specified I2C slave and terminate reading and writing</div>
 +
<div class="mw-collapsible-content" style="text-align: left; padding-left: 5px;">
 +
{| class="wikitable" style="font-size: 14px; background: white;"
 +
|-
 +
! I2C
 +
| The I2C slave to stop
 +
|-
 +
! Return
 +
| ERROR_SUCCESS if completed or another error code on failure
 +
|-
 +
|}
 +
</div></div>
 +
<br />
 +
<div class="toccolours mw-collapsible mw-collapsed" style="border: 1; font-family: arial; padding-top: 0px; padding-bottom: 15px;">
 +
<pre style="border: 0; padding-bottom:0px;">function I2CSlaveRead(I2C:PI2CDevice; Buffer:Pointer; Size:LongWord; var Count:LongWord):LongWord; inline;</pre>
 +
<div style="font-size: 14px; padding-left: 12px;">'''Description:''' Read data from the specified I2C slave</div>
 +
<div class="mw-collapsible-content" style="text-align: left; padding-left: 5px;">
 +
{| class="wikitable" style="font-size: 14px; background: white;"
 +
|-
 +
! I2C
 +
| The I2C slave to read from
 +
|-
 +
! Buffer
 +
| Pointer to a buffer to receive the data
 +
|-
 +
! Size
 +
| The size of the buffer
 +
|-
 +
! Count
 +
| The number of bytes read on return
 +
|-
 +
! Return
 +
| ERROR_SUCCESS if completed or another error code on failure
 +
|-
 +
|}
 +
</div></div>
 +
<br />
 +
<div class="toccolours mw-collapsible mw-collapsed" style="border: 1; font-family: arial; padding-top: 0px; padding-bottom: 15px;">
 +
<pre style="border: 0; padding-bottom:0px;">function I2CSlaveWrite(I2C:PI2CDevice; Buffer:Pointer; Size:LongWord; var Count:LongWord):LongWord; inline;</pre>
 +
<div style="font-size: 14px; padding-left: 12px;">'''Description:''' Write data to the specified I2C slave</div>
 +
<div class="mw-collapsible-content" style="text-align: left; padding-left: 5px;">
 +
{| class="wikitable" style="font-size: 14px; background: white;"
 +
|-
 +
! I2C
 +
| The I2C slave to write to
 +
|-
 +
! Buffer
 +
| Pointer to a buffer of data to transmit
 +
|-
 +
! Size
 +
| The size of the buffer
 +
|-
 +
! Count
 +
| The number of bytes written on return
 +
|-
 +
! Return
 +
| ERROR_SUCCESS if completed or another error code on failure
 +
|-
 +
|}
 +
</div></div>
 +
<br />
 +
<div class="toccolours mw-collapsible mw-collapsed" style="border: 1; font-family: arial; padding-top: 0px; padding-bottom: 15px;">
 +
<pre style="border: 0; padding-bottom:0px;">function I2CSlaveGetAddress(I2C:PI2CDevice):Word; inline;</pre>
 +
<div style="font-size: 14px; padding-left: 12px;">'''Description:''' Get the address for the specified I2C slave</div>
 +
<div class="mw-collapsible-content" style="text-align: left; padding-left: 5px;">
 +
{| class="wikitable" style="font-size: 14px; background: white;"
 +
|-
 +
! I2C
 +
| The I2C slave to get the address from
 +
|-
 +
! Return
 +
| ERROR_SUCCESS if completed or another error code on failure
 +
|-
 +
|}
 +
</div></div>
 +
<br />
 +
<div class="toccolours mw-collapsible mw-collapsed" style="border: 1; font-family: arial; padding-top: 0px; padding-bottom: 15px;">
 +
<pre style="border: 0; padding-bottom:0px;">function I2CSlaveSetAddress(I2C:PI2CDevice; Address:Word):LongWord; inline;</pre>
 +
<div style="font-size: 14px; padding-left: 12px;">'''Description:''' Set the address for the specified I2C slave</div>
 +
<div class="mw-collapsible-content" style="text-align: left; padding-left: 5px;">
 +
{| class="wikitable" style="font-size: 14px; background: white;"
 +
|-
 +
! I2C
 +
| The I2C slave to set the address for
 +
|-
 +
! Address
 +
| The address to set
 +
|-
 +
! Return
 +
| ERROR_SUCCESS if completed or another error code on failure
 +
|-
 +
|}
 +
</div></div>
 +
<br />
 +
<div class="toccolours mw-collapsible mw-collapsed" style="border: 1; font-family: arial; padding-top: 0px; padding-bottom: 15px;">
 +
<pre style="border: 0; padding-bottom:0px;">function I2CSlaveGetProperties(I2C:PI2CDevice; Properties:PI2CProperties):LongWord; inline;</pre>
 +
<div style="font-size: 14px; padding-left: 12px;">'''Description:''' Get the properties for the specified I2C slave</div>
 +
<div class="mw-collapsible-content" style="text-align: left; padding-left: 5px;">
 +
{| class="wikitable" style="font-size: 14px; background: white;"
 +
|-
 +
! I2C
 +
| The I2C slave to get properties from
 +
|-
 +
! Properties
 +
| Pointer to a TI2CProperties structure to fill in
 +
|-
 +
! Return
 +
| ERROR_SUCCESS if completed or another error code on failure
 +
|-
 +
|}
 +
</div></div>
 +
<br />
 +
<div class="toccolours mw-collapsible mw-collapsed" style="border: 1; font-family: arial; padding-top: 0px; padding-bottom: 15px;">
 +
<pre style="border: 0; padding-bottom:0px;">function I2CSlaveCreate:PI2CDevice;</pre>
 +
<div style="font-size: 14px; padding-left: 12px;">'''Description:''' Create a new I2C slave entry</div>
 +
<div class="mw-collapsible-content" style="text-align: left; padding-left: 5px;">
 +
{| class="wikitable" style="font-size: 14px; background: white;"
 +
|-
 +
! Return
 +
| Pointer to new I2C slave entry or nil if I2C could not be created
 +
|-
 +
|}
 +
</div></div>
 +
<br />
 +
<div class="toccolours mw-collapsible mw-collapsed" style="border: 1; font-family: arial; padding-top: 0px; padding-bottom: 15px;">
 +
<pre style="border: 0; padding-bottom:0px;">function I2CSlaveCreateEx(Size:LongWord):PI2CDevice;</pre>
 +
<div style="font-size: 14px; padding-left: 12px;">'''Description:''' Create a new I2C slave entry</div>
 +
<div class="mw-collapsible-content" style="text-align: left; padding-left: 5px;">
 +
{| class="wikitable" style="font-size: 14px; background: white;"
 +
|-
 +
! Size
 +
| Size in bytes to allocate for new I2C (Including the I2C slave entry)
 +
|-
 +
! Return
 +
| Pointer to new I2C slave entry or nil if I2C could not be created
 +
|-
 +
|}
 +
</div></div>
 +
<br />
 +
<div class="toccolours mw-collapsible mw-collapsed" style="border: 1; font-family: arial; padding-top: 0px; padding-bottom: 15px;">
 +
<pre style="border: 0; padding-bottom:0px;">function I2CSlaveDestroy(I2C:PI2CDevice):LongWord; inline;</pre>
 +
<div style="font-size: 14px; padding-left: 12px;">'''Description:''' Destroy an existing I2C slave entry</div>
 +
<div class="mw-collapsible-content" style="text-align: left; padding-left: 5px;">
 +
{| class="wikitable" style="font-size: 14px; background: white;"
 +
|-
 +
! I2C
 +
| The I2C slave to destroy
 +
|-
 +
! Return
 +
| ERROR_SUCCESS if completed or another error code on failure
 +
|-
 +
|}
 +
</div></div>
 +
<br />
 +
<div class="toccolours mw-collapsible mw-collapsed" style="border: 1; font-family: arial; padding-top: 0px; padding-bottom: 15px;">
 +
<pre style="border: 0; padding-bottom:0px;">function I2CSlaveRegister(I2C:PI2CDevice):LongWord; inline;</pre>
 +
<div style="font-size: 14px; padding-left: 12px;">'''Description:''' Register a new I2C slave in the I2C table</div>
 +
<div class="mw-collapsible-content" style="text-align: left; padding-left: 5px;">
 +
{| class="wikitable" style="font-size: 14px; background: white;"
 +
|-
 +
! I2C
 +
| The I2C slave to register
 +
|-
 +
! Return
 +
| ERROR_SUCCESS if completed or another error code on failure
 +
|-
 +
|}
 +
</div></div>
 +
<br />
 +
<div class="toccolours mw-collapsible mw-collapsed" style="border: 1; font-family: arial; padding-top: 0px; padding-bottom: 15px;">
 +
<pre style="border: 0; padding-bottom:0px;">function I2CSlaveDeregister(I2C:PI2CDevice):LongWord; inline;</pre>
 +
<div style="font-size: 14px; padding-left: 12px;">'''Description:''' Deregister an I2C slave from the I2C table</div>
 +
<div class="mw-collapsible-content" style="text-align: left; padding-left: 5px;">
 +
{| class="wikitable" style="font-size: 14px; background: white;"
 +
|-
 +
! I2C
 +
| The I2C slave to deregister
 +
|-
 +
! Return
 +
| ERROR_SUCCESS if completed or another error code on failure
 +
|-
 +
|}
 +
</div></div>
 +
<br />
 +
<div class="toccolours mw-collapsible mw-collapsed" style="border: 1; font-family: arial; padding-top: 0px; padding-bottom: 15px;">
 +
<pre style="border: 0; padding-bottom:0px;">function I2CSlaveFind(I2CId:LongWord):PI2CDevice;</pre>
 +
<div style="font-size: 14px; padding-left: 12px;">'''Description:''' Find an I2C slave by ID in the I2C table</div>
 +
<div class="mw-collapsible-content" style="text-align: left; padding-left: 5px;">
 +
{| class="wikitable" style="font-size: 14px; background: white;"
 +
|-
 +
! I2CId
 +
| The ID number of the I2C slave to find
 +
|-
 +
! Return
 +
| Pointer to I2C slave entry or nil if not found
 +
|-
 +
|}
 +
</div></div>
 +
<br />
 +
<div class="toccolours mw-collapsible mw-collapsed" style="border: 1; font-family: arial; padding-top: 0px; padding-bottom: 15px;">
 +
<pre style="border: 0; padding-bottom:0px;">function I2CSlaveFindByName(const Name:String):PI2CDevice; inline;</pre>
 +
<div style="font-size: 14px; padding-left: 12px;">'''Description:''' Find an I2C slave by name in the device table</div>
 +
<div class="mw-collapsible-content" style="text-align: left; padding-left: 5px;">
 +
{| class="wikitable" style="font-size: 14px; background: white;"
 +
|-
 +
! Name
 +
| The name of the I2C slave to find (eg I2CSlave0)
 +
|-
 +
! Return
 +
| The name of the I2C slave to find (eg I2CSlave0)
 +
|-
 +
|}
 +
</div></div>
 +
<br />
 +
<div class="toccolours mw-collapsible mw-collapsed" style="border: 1; font-family: arial; padding-top: 0px; padding-bottom: 15px;">
 +
<pre style="border: 0; padding-bottom:0px;">function I2CSlaveFindByDescription(const Description:String):PI2CDevice; inline;</pre>
 +
<div style="font-size: 14px; padding-left: 12px;">'''Description:''' Find an I2C slave by description in the device table</div>
 +
<div class="mw-collapsible-content" style="text-align: left; padding-left: 5px;">
 +
{| class="wikitable" style="font-size: 14px; background: white;"
 +
|-
 +
! Description
 +
| The description of the I2C slave to find (eg BCM2837 I2C Slave)
 +
|-
 +
! Return
 +
| Pointer to I2C slave entry or nil if not found
 
|-
 
|-
 
|}
 
|}
Line 1,059: Line 1,344:
 
<pre style="border: 0; padding-bottom:0px;">function I2CDeviceCheck(I2C:PI2CDevice):PI2CDevice;</pre>
 
<pre style="border: 0; padding-bottom:0px;">function I2CDeviceCheck(I2C:PI2CDevice):PI2CDevice;</pre>
 
<div style="font-size: 14px; padding-left: 12px;">'''Description:''' Check if the supplied I2C is in the I2C table</div>
 
<div style="font-size: 14px; padding-left: 12px;">'''Description:''' Check if the supplied I2C is in the I2C table</div>
 +
<div class="mw-collapsible-content" style="text-align: left; padding-left: 5px;">
 +
{| class="wikitable" style="font-size: 14px; background: white;"
 +
|-
 +
! Note
 +
| None documented
 +
|-
 +
|}
 +
</div></div>
 +
<br />
 +
<div class="toccolours mw-collapsible mw-collapsed" style="border: 1; font-family: arial; padding-top: 0px; padding-bottom: 15px;">
 +
<pre style="border: 0; padding-bottom:0px;">function I2CDeviceIsSlave(I2C:PI2CDevice):Boolean;</pre>
 +
<div style="font-size: 14px; padding-left: 12px;">'''Description:''' Check if the supplied I2C is a slave device</div>
 
<div class="mw-collapsible-content" style="text-align: left; padding-left: 5px;">
 
<div class="mw-collapsible-content" style="text-align: left; padding-left: 5px;">
 
{| class="wikitable" style="font-size: 14px; background: white;"
 
{| class="wikitable" style="font-size: 14px; background: white;"

Revision as of 05:08, 28 November 2022

Return to Unit Reference


Description

Ultibo I2C Interface unit

I2C (Inter-Integrated Circuit) is a serial bus for communication between peripheral components.

Originally invented by Phillips the I2C protocol is used by thousands of common chips that perform a wide range of tasks such as real time clocks, temperature and other sensors, small LCD displays and many more.

Each device is assigned a 7bit address which is used by the host (or master) to signal the device that a message written to the bus is intended for that device or that the host wants to read data from that device.

A small number of devices and hosts support 10bit addressing which expands the number of available addresses. The 10bit address format is defined here https://www.i2c-bus.org/addressing/10-bit-addressing/ and the reserved addresses are defined on this page https://www.i2c-bus.org/addressing/

Speeds range from 10Kbps to 3.4Mbps although the typical speed is either 100Kbps or 400Kbps.

This unit implements the standardized interface for I2C devices and allows reading or writing to a specific address, setting a clock rate for the communication and determining device properties.

For the purpose of this interface a device is the I2C controller attached to the local system and may be either a master or a slave. Since the protocol does not include any form of enumeration or identification the interface does not attempt to represent the devices connected to the bus,any driver written to communicate with a connected I2C device should know (or allow configuration of) the address to read and write to and the specific message format required for that device. The Intel System Management Bus (SMBus) is a variation of the I2C bus and in certain cases the two are compatible with each other.

Constants


I2C specific constants I2C_*
I2C_NAME_PREFIX = 'I2C'; Name prefix for I2C Devices
I2CSLAVE_NAME_PREFIX = 'I2CSlave'; Name prefix for I2C Slave Devices


I2C device type I2C_TYPE_*
I2C_TYPE_NONE = 0;  
I2C_TYPE_MASTER = 1;  
I2C_TYPE_SLAVE = 2;  
 
I2C_TYPE_MAX = 2;  
 
I2C Type Names
I2C_TYPE_NAMES:array[I2C_TYPE_NONE..I2C_TYPE_MAX] of String = ('I2C_TYPE_NONE', 'I2C_TYPE_MASTER', 'I2C_TYPE_SLAVE');


I2C device state I2C_STATE_*
I2C_STATE_DISABLED = 0;  
I2C_STATE_ENABLED = 1;  
 
I2C_STATE_MAX = 1;  


I2C device flag I2C_FLAG_*
I2C_FLAG_NONE = $00000000;  
I2C_FLAG_SLAVE = $00000001; Device is a slave not a master
I2C_FLAG_10BIT = $00000002; Device supports 10bit addressing
I2C_FLAG_16BIT = $00000004; Device supports 16bit addressing


I2C logging I2C_LOG_*
I2C_LOG_LEVEL_DEBUG = LOG_LEVEL_DEBUG; I2C debugging messages
I2C_LOG_LEVEL_INFO = LOG_LEVEL_INFO; I2C informational messages, such as a device being attached or detached
I2C_LOG_LEVEL_WARN = LOG_LEVEL_WARN; I2C warning messages
I2C_LOG_LEVEL_ERROR = LOG_LEVEL_ERROR; I2C error messages
I2C_LOG_LEVEL_NONE = LOG_LEVEL_NONE; No I2C messages


Type definitions


I2C properties

PI2CProperties = ^TI2CProperties;

TI2CProperties = record

Flags:LongWord; Device flags (eg I2C_FLAG_SLAVE)
MaxSize:LongWord; Maximum supported data transfer size
MinClock:LongWord; Minimum supported clock rate
MaxClock:LongWord; Maximum supported clock rate
ClockRate:LongWord; Current clock rate
SlaveAddress:Word; Current slave address

I2C enumeration callback

TI2CEnumerate = function(I2C:PI2CDevice; Data:Pointer):LongWord;

I2C notification callback

TI2CNotification = function(Device:PDevice; Data:Pointer; Notification:LongWord):LongWord;

I2C device start

TI2CDeviceStart = function(I2C:PI2CDevice;Rate:LongWord):LongWord;

I2C device stop

TI2CDeviceStop = function(I2C:PI2CDevice):LongWord;

I2C device read

TI2CDeviceRead = function(I2C:PI2CDevice; Address:Word; Buffer:Pointer; Size:LongWord; var Count:LongWord):LongWord;

I2C device write

TI2CDeviceWrite = function(I2C:PI2CDevice; Address:Word; Buffer:Pointer; Size:LongWord; var Count:LongWord):LongWord;

I2C device write read

TI2CDeviceWriteRead = function(I2C:PI2CDevice; Address:Word; Initial:Pointer; Len:LongWord; Data:Pointer; Size:LongWord; var Count:LongWord):LongWord;

I2C device write write

TI2CDeviceWriteWrite = function(I2C:PI2CDevice; Address:Word; Initial:Pointer; Len:LongWord; Data:Pointer; Size:LongWord; var Count:LongWord):LongWord;

I2C device get rate

TI2CDeviceGetRate = function(I2C:PI2CDevice):LongWord;

I2C device set rate

TI2CDeviceSetRate = function(I2C:PI2CDevice; Rate:LongWord):LongWord;

I2C device get address

TI2CDeviceGetAddress = function(I2C:PI2CDevice):Word;

I2C device set address

TI2CDeviceSetAddress = function(I2C:PI2CDevice; Address:Word):LongWord;

I2C device get properties

TI2CDeviceGetProperties = function(I2C:PI2CDevice; Properties:PI2CProperties):LongWord;

I2C device

PI2CDevice = ^TI2CDevice;

TI2CDevice = record

Device Properties
Device:TDevice; The Device entry for this I2C
I2C Properties
I2CId:LongWord; Unique Id of this I2C in the I2C table
I2CState:LongWord; I2C state (eg I2C_STATE_ENABLED)
DeviceStart:TI2CDeviceStart; A Device specific DeviceStart method implementing the standard I2C device interface (Mandatory)
DeviceStop:TI2CDeviceStop; A Device specific DeviceStop method implementing the standard I2C device interface (Mandatory)
DeviceRead:TI2CDeviceRead; A Device specific DeviceRead method implementing the standard I2C device interface (Mandatory)
DeviceWrite:TI2CDeviceWrite; A Device specific DeviceWrite method implementing the standard I2C device interface (Mandatory)
DeviceWriteRead:TI2CDeviceWriteRead; A Device specific DeviceWriteRead method implementing the standard I2C device interface (Or nil if the default method is suitable)
DeviceWriteWrite:TI2CDeviceWriteWrite; A Device specific DeviceWriteWrite method implementing the standard I2C device interface (Or nil if the default method is suitable)
DeviceGetRate:TI2CDeviceGetRate; A Device specific DeviceGetRate method implementing the standard I2C device interface (Or nil if the default method is suitable)
DeviceSetRate:TI2CDeviceSetRate; A Device specific DeviceSetRate method implementing the standard I2C device interface (Or nil if the default method is suitable)
DeviceGetAddress:TI2CDeviceGetAddress; A Device specific DeviceGetAddress method implementing the standard I2C device interface (Or nil if the default method is suitable)
DeviceSetAddress:TI2CDeviceSetAddress; A Device specific DeviceSetAddress method implementing the standard I2C device interface (Or nil if the default method is suitable)
DeviceGetProperties:TI2CDeviceGetProperties; A Device specific DeviceGetProperties method implementing the standard I2C device interface (Or nil if the default method is suitable)
Statistics Properties
ReadCount:LongWord;  
WriteCount:LongWord;  
ReadErrors:LongWord;  
WriteErrors:LongWord;  
Driver Properties
Lock:TMutexHandle; Device lock
Wait:TSemaphoreHandle; Read/Write wait event
ClockRate:LongWord; Clock rate (Hz)
SlaveAddress:Word; Slave address
Properties:TI2CProperties; Device properties
Internal Properties
Prev:PI2CDevice; Previous entry in I2C table
Next:PI2CDevice; Next entry in I2C table


Public variables


I2C logging

I2C_DEFAULT_LOG_LEVEL:LongWord = I2C_LOG_LEVEL_DEBUG; Minimum level for I2C messages. Only messages with level greater than or equal to this will be printed.
I2C_LOG_ENABLED:Boolean;


Function declarations


Initialization functions 

procedure I2CInit;
Description: Initialize the I2C unit and I2C device table
Note Called only during system startup


I2C functions 

function I2CDeviceStart(I2C:PI2CDevice; Rate:LongWord):LongWord;
Description: Start the specified I2C device ready for reading and writing
I2C The I2C device to start
Rate The clock rate to set for the device (0 to use the default rate)
Return ERROR_SUCCESS if completed or another error code on failure 


function I2CDeviceStop(I2C:PI2CDevice):LongWord;
Description: Stop the specified I2C device and terminate reading and writing
I2C The I2C device to stop
Return ERROR_SUCCESS if completed or another error code on failure 


function I2CDeviceRead(I2C:PI2CDevice; Address:Word; Buffer:Pointer; Size:LongWord; var Count:LongWord):LongWord;
Description: Read data from the specified I2C device
I2C The I2C device to read from
Address The slave address to read from (I2C_ADDRESS_INVALID to use the current address)
Buffer Pointer to a buffer to receive the data
Size The size of the buffer
Count The number of bytes read on return
Return ERROR_SUCCESS if completed or another error code on failure 


function I2CDeviceWrite(I2C:PI2CDevice; Address:Word; Buffer:Pointer; Size:LongWord; var Count:LongWord):LongWord;
Description: Write data to the specified I2C device
I2C The I2C device to write to
Address The slave address to write to (I2C_ADDRESS_INVALID to use the current address)
Buffer Pointer to a buffer of data to transmit
Size The size of the buffer
Count The number of bytes written on return
Return ERROR_SUCCESS if completed or another error code on failure 


function I2CDeviceWriteRead(I2C:PI2CDevice; Address:Word; Initial:Pointer; Len:LongWord; Data:Pointer; Size:LongWord; var Count:LongWord):LongWord;
Description: Write data to and Read data from the specified I2C device in one operation
I2C The I2C device to write to and read from
Address The slave address to write to (I2C_ADDRESS_INVALID to use the current address)
Initial Pointer to the initial buffer to transmit
Len The size of the initial buffer
Data Pointer to a buffer to receive the data
Size The size of the data buffer
Count The number of bytes read on return
Return ERROR_SUCCESS if completed or another error code on failure
Note Useful for devices that require a register address specified before a read (eg EEPROM devices) 


function I2CDeviceWriteWrite(I2C:PI2CDevice; Address:Word; Initial:Pointer; Len:LongWord; Data:Pointer; Size:LongWord; var Count:LongWord):LongWord;
Description: Write 2 data blocks to the specified I2C device in one operation
I2C The I2C device to write to
Address The slave address to write to (I2C_ADDRESS_INVALID to use the current address)
Initial Pointer to the initial buffer to transmit
Len The size of the initial buffer
Data Pointer to a buffer of data to transmit
Size The size of the data buffer
Count The number of bytes of data written on return
Return ERROR_SUCCESS if completed or another error code on failure
Note Useful for devices that require a register address specified before a write (eg EEPROM devices) 


function I2CDeviceGetRate(I2C:PI2CDevice):LongWord;
Description: Get the clock rate of the specified I2C device
I2C The I2C device to get the clock rate from
Return The clock rate in Hz or 0 on failure 


function I2CDeviceSetRate(I2C:PI2CDevice; Rate:LongWord):LongWord;
Description: Set the clock rate for the specified I2C device
I2C The I2C device to set the clock rate for
Rate The clock rate to set in Hz
Return ERROR_SUCCESS if completed or another error code on failure 


function I2CDeviceGetAddress(I2C:PI2CDevice):Word;
Description: Get the slave address for the specified I2C device
I2C The I2C device to get the slave address from
Return The slave address or I2C_ADDRESS_INVALID on failure 


function I2CDeviceSetAddress(I2C:PI2CDevice; Address:Word):LongWord;
Description: Set the slave address for the specified I2C device
I2C The I2C device to set the slave address for
Address The slave address to set
Return ERROR_SUCCESS if completed or another error code on failure 


function I2CDeviceProperties(I2C:PI2CDevice; Properties:PI2CProperties):LongWord; inline;
Description: Get the properties for the specified I2C device
I2C The I2C device to get properties from
Properties Pointer to a TI2CProperties structure to fill in
Return ERROR_SUCCESS if completed or another error code on failure
Note Replaced by I2CDeviceGetProperties for consistency 


function I2CDeviceGetProperties(I2C:PI2CDevice; Properties:PI2CProperties):LongWord;
Description: Get the properties for the specified I2C device
I2C The I2C device to get properties from
Properties Pointer to a TI2CProperties structure to fill in
Return ERROR_SUCCESS if completed or another error code on failure 


function I2CDeviceCreate:PI2CDevice;
Description: Create a new I2C entry
Return Pointer to new I2C entry or nil if I2C could not be created 


function I2CDeviceCreateEx(Size:LongWord):PI2CDevice;
Description: Create a new I2C entry
Size Size in bytes to allocate for new I2C (Including the I2C entry)
Return Pointer to new I2C entry or nil if I2C could not be created 


function I2CDeviceDestroy(I2C:PI2CDevice):LongWord;
Description: Destroy an existing I2C entry
I2C The I2C device to destroy
Return ERROR_SUCCESS if completed or another error code on failure 


function I2CDeviceRegister(I2C:PI2CDevice):LongWord;
Description: Register a new I2C in the I2C table
I2C The I2C device to register
Return ERROR_SUCCESS if completed or another error code on failure 


function I2CDeviceDeregister(I2C:PI2CDevice):LongWord;
Description: Deregister an I2C from the I2C table
I2C The I2C device to deregister
Return ERROR_SUCCESS if completed or another error code on failure 


function I2CDeviceFind(I2CId:LongWord):PI2CDevice;
Description: Find an I2C device by ID in the I2C table
I2CId The ID number of the I2C device to find
Return Pointer to I2C device entry or nil if not found 


function I2CDeviceFindByName(const Name:String):PI2CDevice; inline;
Description: Find an I2C device by name in the device table
Name The name of the I2C device to find (eg I2C0)
Return Pointer to I2C device entry or nil if not found 


function I2CDeviceFindByDescription(const Description:String):PI2CDevice; inline;
Description: Find an I2C device by description in the device table
Description The description of the I2C to find (eg BCM2837 BSC1 Master I2C)
Return Pointer to I2C device entry or nil if not found 


function I2CDeviceEnumerate(Callback:TI2CEnumerate; Data:Pointer):LongWord;
Description: Enumerate all I2C devices in the I2C table
Callback The callback function to call for each I2C device in the table
Data A private data pointer to pass to callback for each I2C device in the table
Return ERROR_SUCCESS if completed or another error code on failure 


function I2CDeviceNotification(I2C:PI2CDevice; Callback:TI2CNotification; Data:Pointer; Notification,Flags:LongWord):LongWord;
Description: Register a notification for I2C device changes
Device The I2C device to notify changes for (Optional, pass nil for all I2C devices)
Callback The function to call when a notification event occurs
Data A private data pointer to pass to callback when a notification event occurs
Notification The events to register for notification of (eg DEVICE_NOTIFICATION_REGISTER)
Flags The flags to control the notification (eg NOTIFIER_FLAG_WORKER)


I2C slave functions 

function I2CSlaveStart(I2C:PI2CDevice):LongWord; inline;
Description: Start the specified I2C slave ready for reading and writing
I2C The I2C slave to start
Return ERROR_SUCCESS if completed or another error code on failure 


function I2CSlaveStop(I2C:PI2CDevice):LongWord; inline;
Description: Stop the specified I2C slave and terminate reading and writing
I2C The I2C slave to stop
Return ERROR_SUCCESS if completed or another error code on failure 


function I2CSlaveRead(I2C:PI2CDevice; Buffer:Pointer; Size:LongWord; var Count:LongWord):LongWord; inline;
Description: Read data from the specified I2C slave
I2C The I2C slave to read from
Buffer Pointer to a buffer to receive the data
Size The size of the buffer
Count The number of bytes read on return
Return ERROR_SUCCESS if completed or another error code on failure 


function I2CSlaveWrite(I2C:PI2CDevice; Buffer:Pointer; Size:LongWord; var Count:LongWord):LongWord; inline;
Description: Write data to the specified I2C slave
I2C The I2C slave to write to
Buffer Pointer to a buffer of data to transmit
Size The size of the buffer
Count The number of bytes written on return
Return ERROR_SUCCESS if completed or another error code on failure 


function I2CSlaveGetAddress(I2C:PI2CDevice):Word; inline;
Description: Get the address for the specified I2C slave
I2C The I2C slave to get the address from
Return ERROR_SUCCESS if completed or another error code on failure 


function I2CSlaveSetAddress(I2C:PI2CDevice; Address:Word):LongWord; inline;
Description: Set the address for the specified I2C slave
I2C The I2C slave to set the address for
Address The address to set
Return ERROR_SUCCESS if completed or another error code on failure 


function I2CSlaveGetProperties(I2C:PI2CDevice; Properties:PI2CProperties):LongWord; inline;
Description: Get the properties for the specified I2C slave
I2C The I2C slave to get properties from
Properties Pointer to a TI2CProperties structure to fill in
Return ERROR_SUCCESS if completed or another error code on failure 


function I2CSlaveCreate:PI2CDevice;
Description: Create a new I2C slave entry
Return Pointer to new I2C slave entry or nil if I2C could not be created 


function I2CSlaveCreateEx(Size:LongWord):PI2CDevice;
Description: Create a new I2C slave entry
Size Size in bytes to allocate for new I2C (Including the I2C slave entry)
Return Pointer to new I2C slave entry or nil if I2C could not be created 


function I2CSlaveDestroy(I2C:PI2CDevice):LongWord; inline;
Description: Destroy an existing I2C slave entry
I2C The I2C slave to destroy
Return ERROR_SUCCESS if completed or another error code on failure 


function I2CSlaveRegister(I2C:PI2CDevice):LongWord; inline;
Description: Register a new I2C slave in the I2C table
I2C The I2C slave to register
Return ERROR_SUCCESS if completed or another error code on failure 


function I2CSlaveDeregister(I2C:PI2CDevice):LongWord; inline;
Description: Deregister an I2C slave from the I2C table
I2C The I2C slave to deregister
Return ERROR_SUCCESS if completed or another error code on failure 


function I2CSlaveFind(I2CId:LongWord):PI2CDevice;
Description: Find an I2C slave by ID in the I2C table
I2CId The ID number of the I2C slave to find
Return Pointer to I2C slave entry or nil if not found 


function I2CSlaveFindByName(const Name:String):PI2CDevice; inline;
Description: Find an I2C slave by name in the device table
Name The name of the I2C slave to find (eg I2CSlave0)
Return The name of the I2C slave to find (eg I2CSlave0) 


function I2CSlaveFindByDescription(const Description:String):PI2CDevice; inline;
Description: Find an I2C slave by description in the device table
Description The description of the I2C slave to find (eg BCM2837 I2C Slave)
Return Pointer to I2C slave entry or nil if not found


RTL I2C functions 

function SysI2CAvailable:Boolean;
Description: Check if an I2C device is available
Note None documented 


function SysI2CStart(Rate:LongWord):LongWord;
Description: Start the default I2C device ready for reading and writing
Rate The clock rate to set for the device (0 to use the default rate)
Return ERROR_SUCCESS if completed or another error code on failure 


function SysI2CStop:LongWord;
Description: Stop the default I2C device and terminate reading and writing
Return ERROR_SUCCESS if completed or another error code on failure 


function SysI2CRead(Address:Word; Buffer:Pointer; Size:LongWord; var Count:LongWord):LongWord;
Description: Read data from the default I2C device
Address The slave address to read from (I2C_ADDRESS_INVALID to use the current address)
Buffer Pointer to a buffer to receive the data
Size The size of the buffer
Count The number of bytes read on return
Return ERROR_SUCCESS if completed or another error code on failure 


function SysI2CWrite(Address:Word; Buffer:Pointer; Size:LongWord; var Count:LongWord):LongWord;
Description: Write data to the default I2C device
Address The slave address to write to (I2C_ADDRESS_INVALID to use the current address)
Buffer Pointer to a buffer of data to transmit
Size The size of the buffer
Count The number of bytes written on return
Return ERROR_SUCCESS if completed or another error code on failure 


function SysI2CWriteRead(Address:Word; Initial:Pointer; Len:LongWord; Data:Pointer; Size:LongWord; var Count:LongWord):LongWord;
Description: Write data to and Read data from the default I2C device in one operation
Address The slave address to write to (I2C_ADDRESS_INVALID to use the current address)
Initial Pointer to the initial buffer to transmit
Len The size of the initial buffer
Data Pointer to a buffer to receive the data
Size The size of the data buffer
Count The number of bytes read on return
Return ERROR_SUCCESS if completed or another error code on failure
Note Useful for devices that require a register address specified before a read (eg EEPROM devices) 


function SysI2CWriteWrite(Address:Word; Initial:Pointer; Len:LongWord; Data:Pointer; Size:LongWord; var Count:LongWord):LongWord;
Description: Write 2 data blocks to the default I2C device in one operation
Address The slave address to write to (I2C_ADDRESS_INVALID to use the current address)
Initial Pointer to the initial buffer to transmit
Len The size of the initial buffer
Data Pointer to a buffer of data to transmit
Size The size of the data buffer
Count The number of bytes of data written on return
Return ERROR_SUCCESS if completed or another error code on failure
Note Useful for devices that require a register address specified before a write (eg EEPROM devices) 


function SysI2CGetRate:LongWord;
Description: Get the clock rate of the default I2C device
Return The clock rate in Hz or 0 on failure 


function SysI2CSetRate(Rate:LongWord):LongWord;
Description: Set the clock rate for the default I2C device
Rate The clock rate to set in Hz
Return ERROR_SUCCESS if completed or another error code on failure 


function SysI2CGetAddress:Word;
Description: Get the slave address for the default I2C device
Return The slave address or I2C_ADDRESS_INVALID on failure 


function SysI2CSetAddress(Address:Word):LongWord;
Description: Set the slave address for the default I2C device
Address The slave address to set
Return ERROR_SUCCESS if completed or another error code on failure


I2C helper functions 

function I2CGetCount:LongWord; inline;
Description: Get the current I2C count
Note None documented 


function I2CDeviceGetDefault:PI2CDevice; inline;
Description: Get the current default I2C device
Note None documented 


function I2CDeviceSetDefault(I2C:PI2CDevice):LongWord;
Description: Set the current default I2C device
Note None documented 


function I2CDeviceCheck(I2C:PI2CDevice):PI2CDevice;
Description: Check if the supplied I2C is in the I2C table
Note None documented 


function I2CDeviceIsSlave(I2C:PI2CDevice):Boolean;
Description: Check if the supplied I2C is a slave device
Note None documented 


function I2CTypeToString(I2CType:LongWord):String;
Description: Convert an I2C type value to a string
Note None documented 


function I2CStateToString(I2CState:LongWord):String;
Description: Convert an I2C state value to a string
Note None documented 


function I2CIs7BitAddress(Address:Word):Boolean;
Description: Determine if the supplied address is a 7bit address
Note None documented 


function I2CIs10BitAddress(Address:Word):Boolean;
Description: Determine if the supplied address is a 10bit address
Note None documented 


procedure I2CLog(Level:LongWord; I2C:PI2CDevice; const AText:String);
Description: To be documented
Note None documented 


procedure I2CLogInfo(I2C:PI2CDevice; const AText:String); inline;
Description: To be documented
Note None documented 


procedure I2CLogWarn(I2C:PI2CDevice; const AText:String); inline;
Description: To be documented
Note None documented 


procedure I2CLogError(I2C:PI2CDevice; const AText:String); inline;
Description: To be documented
Note None documented 


procedure I2CLogDebug(I2C:PI2CDevice; const AText:String); inline;
Description: To be documented
Note None documented


Return to Unit Reference

Retrieved from "https://ultibo.org/mediawiki_ultibo_org/index.php?title=Unit_I2C&oldid=5673"