Modbus RTU Read multiple registers at once

[radiator]

Hi,
I'm looking for a way how to read multiple input registers at once to reduce bus load. As basis i use the Master example. As long i read only one register it works fine.

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{ CID_UL1N, STR("UL1N"), STR("V"), MB_DEVICE_ADDR1, MB_PARAM_INPUT, 0, 2, INPUT_OFFSET(input_data0), PARAM_TYPE_ASCII, 4, OPTS( 0, 0, 0 ), PAR_PERMS_READ_WRITE_TRIGGER }

As soon i change the parameter descriptor to read 4 words the ESP reboots when the data is received.

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{ CID_UL1N, STR("UL1N"), STR("V"), MB_DEVICE_ADDR1, MB_PARAM_INPUT, 0, 4, INPUT_OFFSET(input_data), PARAM_TYPE_ASCII, 8, OPTS( 0, 0, 0 ), PAR_PERMS_READ_WRITE_TRIGGER }

The request is sent out OK and also the response of the slave is ok but the ESP reboots when data is received. I also defined the input data as an array so there shall be enough space to hold the received data. Also tried with different PARM_TYPE's

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typedef struct
{
    uint16_t input_data[16]; // 0
    
} input_reg_params_t;

I have disabled all the received data handling i do only call:

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err = mbc_master_get_cid_info(cid, &param_descriptor);

Works fine

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mbc_master_get_parameter(cid, (char*)param_descriptor->param_key,(uint8_t*)&value, &type);

crashes as soon as the slave answers.

request: 0x01 0x04 0x00 0x00 0x00 0x04 0xf1 0xc9
answer: 0x01 0x04 0x08 0x43 0x69 0xa0 0xba 0x00 0x00 0x00 0x00 0x58 0x55

Any help is appreciated as it looks like that i did not get something. crashing the device by receiving some data is quite strange to me.

[radiator]

Issue fixed.
Had bug in the definition of the

value

.

[pushkarvish4853]

Issue fixed.
Had bug in the definition of the

value

.

Code: [Select all] [Expand/Collapse]

1. Can you please help me how did you changed value definition so it worked actually I am too stuck at the same point, Thank you in advance.

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