Vicente Jimenez
/
SLab_Python
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protocol.txt
- Committer:
- vic20
- Date:
- 2018-02-11
- Revision:
- 1:d81bef65eece
- Parent:
- 0:39a545e08ccd
File content as of revision 1:d81bef65eece:
This document describes the communication protocol between
Python and the Hardware Board
Protocol is Client/Server
The board operates as the server and responds to requests
from the Python code in n a PC
All communications use a simple XOR on all bytes to generate
the CRC. The CRC is the last byte send in any transmission.
Format of data:
byte : 1 Byte
u16 : 2 Bytes little endian ( L followed by H)
float : 3 Bytes : Byte : Exponent Offset 128
u16 : Mantissa Offset 20000
Before each command:
P : init P-TxCRC,P-RxCRC
B : init B-RxCRC,B-TxCRC
COMMANDS ---------------------------------------------------
Command 'F' Get Firmware String
This command is the only one without CRC
P -> B : byte('F')
B -> P : Firmware String than ends with "\n\r"
Command 'M' Get Magic Code
P -> B : byte('M')
P-TxCRC
B : if P-CRC != B-RxCRC
B -> P : ECRC
B -> P : B-TxCRC
P : Check CRC
else
B -> P : ACK
B -> P : 4 byte magic code
B-TxCRC
P : Check CRC
P : Check Magic
Command 'I' Get Board Capabilities
P -> B : byte('I')
P-TxCRC
B : if P-CRC != B-RxCRC
B -> P : ECRC
B -> P : B-TxCRC
P : Check CRC
else
B -> P : ACK
B -> P : byte(Number of DACs)
byte(Number of ADCs)
u16(Unified Buffer Size)
float(Max Sample Time)
float(Min Sample Time)
float(VDD)
float(Max Sample Freq)
float(VREF)
byte(dac_bits)
byte(adc_bits)
B-TxCRC
Command 'L' Get Pin List
P -> B : byte('L')
P-TxCRC
B : if P-CRC != B-RxCRC
B -> P : ECRC
B -> P : B-TxCRC
else
B -> P : ACK
Pin list String that ends with $
B-TxCRC
Command 'A' ADC Read
P -> B : byte('A')
byte(channel)
P-TxCRC
B : if P-CRC != B-RxCRC
B -> P : ECRC
B-TxCRC
else if not valid channel
B -> P : NACK
B-TxCRC
else
B -> P : ACK
U16(Read ADC Value)
B-TxCRC
Command 'D' DAC Write
P -> B : byte('D')
byte(channel)
u16(value)
P-TxCRC
B : if P-CRC != B-RxCRC
B -> P : ECRC
B-TxCRC
else if not valid channel
B -> P : NACK
B-TxCRC
else
B -> P : ACK
B-TxCRC
Command 'R' Set Sample Time
P -> B : byte('R')
float(Sample Time)
P-TxCRC
B : if P-CRC != B-RxCRC
B -> P : ECRC
B-TxCRC
else if not valid sample time
B -> P : NACK
B-TxCRC
else
B -> P : ACK
B-TxCRC
Command 'S' Set Storage
P -> B : byte('S')
byte(Number Analog)
byte(Number Digital)
U16(Number Samples)
P-TxCRC
B : if P-CRC != B-RxCRC
B -> P : ECRC
B-TxCRC
else if not valid
B -> P : NACK
B-TxCRC
else
B -> P : ACK
B-TxCRC
Command 'Y' Async Read
P -> B : byte('Y')
P-TxCRC
B : if P-CRC != B-RxCRC
B -> P : ECRC
B-TxCRC
else
B -> P : ACK
<Dump In Buffer>
B-TxCRC
Command 'G' Triggered Read
P -> B : byte('G')
U16(Trigger)
Byte(mode)
Byte(timeout)
P-TxCRC
B : if P-CRC != B-RxCRC
B -> P : ECRC
B-TxCRC
else if bad mode
B -> P : NACK
B-TxCRC
else
B -> P : ACK
<Dump Triggered In Buffer>
B-TxCRC
Command 'P' Step Response
P -> B : byte('P')
U16(Step Value)
P-TxCRC
B : if P-CRC != B-RxCRC
B -> P : ECRC
B-TxCRC
else
B -> P : ACK
<Dump In Buffer>
B-TxCRC
Command 'W' Load Wavetable
P -> B : byte('W')
U16(Table Size)
if bad Table Size
B -> P : NACK
B-TxCRC
else
P -> B : Table of U16 values
B : if P-CRC != B-RxCRC
B -> P : ECRC
B-TxCRC
B -> P : ACK
B-TxCRC
Command 'w' Load Secondary Wavetable
P -> B : byte('W')
U16(Table Size)
if bad Table Size
B -> P : NACK
B-TxCRC
else
P -> B : Table of U16 values
B : if P-CRC != B-RxCRC
B -> P : ECRC
B-TxCRC
B -> P : ACK
B-TxCRC
Command 'V' Wave Response
P -> B : byte('V')
U16(Number of Waves)
P-TxCRC
B : if P-CRC != B-RxCRC
B -> P : ECRC
B-TxCRC
else
B -> P : ACK
<Dump In buffer>
B-TxCRC
Command 'v' Dual Wave Response
P -> B : byte('V')
U16(Number of Waves)
P-TxCRC
B : if P-CRC != B-RxCRC
B -> P : ECRC
B-TxCRC
else
B -> P : ACK
<Dump In buffer>
B-TxCRC
Command 'Q' Wave Play
P -> B : byte('Q')
U16(Number of Waves)
P-TxCRC
B : if P-CRC != B-RxCRC
B -> P : ECRC
B-TxCRC
else
B -> P : ACK
if halt TRAN_HALT
else TRAN_OK
B-TxCRC
Command 'q' Dual Wave Play
P -> B : byte('q')
U16(Number of Waves)
P-TxCRC
B : if P-CRC != B-RxCRC
B -> P : ECRC
B-TxCRC
else
B -> P : ACK
if halt TRAN_HALT
else TRAN_OK
B-TxCRC
Command 'X' Single Wave Response
P -> B : byte('X')
Byte(Channel to read)
U16(Number of Waves)
P-TxCRC
B : if P-CRC != B-RxCRC
B -> P : ECRC
B-TxCRC
else
B -> P : ACK
<Dump In buffer>
B-TxCRC
Command 'E' Soft Reset
P -> B : byte('E')
P-TxCRC
B : if P-CRC != B-RxCRC
B -> P : ECRC
B-TxCRC
else
B -> P : ACK
B-TxCRC
Command 'H' Digital I/O Mode
P -> B : byte('H')
byte(line)
byte(mode)
P-TxCRC
B : if P-CRC != B-RxCRC
B -> P : ECRC
B-TxCRC
else if not valid channel or mode
B -> P : NACK
B-TxCRC
else
B -> P : ACK
B-TxCRC
Command 'J' Digital I/O Write
P -> B : byte('J')
byte(line)
byte(value)
P-TxCRC
B : if P-CRC != B-RxCRC
B -> P : ECRC
B-TxCRC
else if not valid channel
B -> P : NACK
B-TxCRC
else
B -> P : ACK
B-TxCRC
Command 'K' Digital I/O Read
P -> B : byte('J')
byte(line)
P-TxCRC
B : if P-CRC != B-RxCRC
B -> P : ECRC
B-TxCRC
else if not valid channel
B -> P : NACK
B-TxCRC
else
B -> P : ACK
byte(line value)
B-TxCRC
Command 'N' Number of ADC readings
P -> B : byte('N')
u16(n)
P-TxCRC
B : if P-CRC != B-RxCRC
B -> P : ECRC
B-TxCRC
else
B -> P : ACK
B-TxCRC
<Dump In Buffer>
if halt
B -> P : TRAN_HALT
if overrun
B -> P : TRAN_OVERRUN
else
B -> P : TRAN_OK
Byte(Number Analog)
Byte(Number Digital)
U16(Number Samples)
All Samples in U16
<Dump Triggered In Buffer>
if halt
B -> P : TRAN_HALT
if overrun
B -> P : TRAN_OVERRUN
if timeout
B -> P : TRAN_TIMEOUT
else
B -> P : TRAN_OK
Byte(Number Analog)
Byte(Number Digital)
U16(Number Samples)
All Samples in U16