Mesa modbus and pktUart

Debug should print the sent data in any case

Did you try different parity options?

EDIT:
Actually the commands in your .mod file don't make sense to me:

Function 3 is read multiple registers...

// Lichuan A5 AC Servo Drive Driver
#define MAX_MSG_LEN 16   // may be increased if necessary to max 251
#define DEBUG 3

static const hm2_modbus_chan_descriptor_t channels = {
/*  {TYPE,     FUNC, ADDR,   COUNT, pin_name} */
    {HAL_U32,   3,   0x9C8, 1,     "speed-actual"},
    {HAL_U32,   3,   0x9C9, 1,     "speed-instruction"},
    {HAL_U32,   3,   0x9CA, 1,     "torque-instruction"},
    {HAL_U32,   3,   0x9D4, 1,     "avg-load-rate"},
    {HAL_U32,   3,   0x9E0, 1,     "phase-current"},
    {HAL_U32,   3,   0x9E2, 1,     "bus-voltage"},
    {HAL_U32,   6,   0x9E3, 1,     "tempreture"},
};
 

Ok I did a clean install with linuxcnc 2.10pre, rebuild my driver

I run linuxcnc in terminal and started from parity 0..2 and for each change i ran through the 4 options on my servo drive waited a min or two then went to next option but get the same on all options :

 

A and B signals still looks good :

 
 

Where did you get the function numbers from?
Are all except the last read functions?

Also looks like you lost the pulldown on B
 

I decided to make video too long to write :



Feedback would be appreciated.

How did you get the function numbers?
(they were 3 initially except for the last=6 and then 4 in your later .mod file)

As you pointed out 3 is for Reading multiple holding registers i changed to 4 to read each individual register to get a hal varible. 6 is for writing single register 1227 controls my spindle that is 0x4cb in hex

Actually, looking at earlier scope shots, I think you have an issue with
your firmware:

(baud rate is ~16X too low)

This may mean you are using relative current source but don't have the
latest pktuart versions (2) in the pinout file

Can help me with "pktuart versions (2)" please ?

Do i have to change the pin description ?

No, the module description section needs to change:
                                
(PktUARTTTag,            x"02",    ClockLowTag,        x"01",    PktUARTTDataAddr&PadT,            PktUARTTNumRegs,        x"00",    PktUARTTMPBitMask),
(PktUARTRTag,            x"02",    ClockLowTag,        x"01",    PktUARTRDataAddr&PadT,            PktUARTRNumRegs,        x"00",   PktUARTRMPBitMask),