LabJack UE9 - Page 73

Command:
Byte
0
Checksum8
1
0xF8
2
0x01
3
0x16
4
Checksum16 (LSB)
5
Checksum16 (MSB)
6
0x00
7
Flush
Response:
Byte
0
Checksum8
1
0xF8
2
0x11
3
0x16
4
Checksum16 (LSB)
5
Checksum16 (MSB)
6
Errorcode
7
NumAsynchBytesInRXBuffer
8
AsynchByte0
...
...
39
AsynchByte31
Flush: If nonzero, the entire 256-byte RX buffer is emptied. If there are more than 32 bytes in the buffer that data is lost.
NumAsynchBytesInRXBuffer: Returns the number of bytes in the buffer before this read.
AsynchByte#: Returns the 32 oldest bytes from the RX buffer.
5.3.20 - I²C
Control command sends and receives serial data using I²C synchronous communication.
Command:
Byte
0
Checksum8
1
0xF8
2
4 + NumI2CWordsSend
3
0x3B
4
Checksum16 (LSB)
5
Checksum16 (MSB)
6
I2COptions
Bits 7-5: Reserved
Bit 3: Enable clock streching.
Bit 2: No stop when restarting.
Bit 1: ResetAtStart
Bit 0: Reserved
7
SpeedAdjust
8
SDAPinNum
9
SCLPInNum
10
AddressByte
11
Reserved
12
NumI2CBytesToSend
13
NumI2CBytesToReceive
14
I2CByte0
...
...
Response:
Byte
0
Checksum8
1
0xF8
2
3 + NumI2CWordsSend
3
0x3B
4
Checksum16 (LSB)
5
Checksum16 (MSB)
6
Errorcode
7
Reserved
8
AckArray0
9
AckArray1
10
AckArray2
11
AckArray3
12
I2CByte0
...
...
NumI2CWordsSend: This is the number of I2C bytes to send divided by 2. If the number of bytes is odd, round up and add
an extra zero to the packet. This parameter is actually just to specify the size of this packet, as the NumI2CbytesToSend
parameter below actually specifies how many bytes will be sent.
I2COptions: If ResetAtStart is true, an I2C bus reset will be done before communicating.
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