I need to write and read registers from a serial device. Everything works fine, but I need to store the messages in a variable. For example:
instrument = minimalmodbus.Instrument("/dev/ttyUSB0", 1, minimalmodbus.MODE_ASCII, debug=True)
instrument.serial.baudrate = 9600
instrument.serial.bytesize = serial.EIGHTBITS
instrument.serial.parity = serial.PARITY_NONE
instrument.serial.stopbits = serial.STOPBITS_ONE
instrument.serial.timeout = 2
r = instrument.read_register(1, functioncode=3)
print(r)
What I get is
MinimalModbus debug mode. Create serial port /dev/ttyUSB0
MinimalModbus debug mode. Will write to instrument (expecting 15 bytes back): ':010300010001FA\r\n' (3A 30 31 30 33 30 30 30 31 30 30 30 31 46 41 0D 0A)
MinimalModbus debug mode. Clearing serial buffers for port /dev/ttyUSB0
MinimalModbus debug mode. Sleeping 3.71 ms before sending. Minimum silent period: 4.01 ms, time since read: 0.30 ms.
MinimalModbus debug mode. Response from instrument: ':0103020000FA\r\n' (3A 30 31 30 33 30 32 30 30 30 30 46 41 0D 0A) (15 bytes), roundtrip time: 31.7 ms. Timeout for reading: 2000.0 ms.
0
which is correct; what I need is to store ':010300010001FA\r\n' and ':0103020000FA\r\n' in a variable, and possibly also the number of bytes expected back.
How can I do it? I didn't find anything on the documentation about this
Option 1) Modify the library to return the "answer" variable from private function _communicate to your program.
Option 2) Save the debug log output to a variable and filter this variable for the string.