alisitsyn
commented
1 month ago @yel-best ,
- I am currently doing modbus connection with some PLC devices. I need to see some detailed logs. For example, the sent message "01 03 A0 80 00 01 A7 E2" and then the
The logging for Modbus can be enabled in menuconfig setting the log verbosity. This enables the logging of sent/received PDU frames. The ADU frame logging is removed from the port layer because the log might get cluttered. It is also possible to remove some messages from log.
In addition, the example does not seem to explain how to convert the value.
The code you are looking for is not good example because it is test code and it should not be described for user. This uses the macro which is an analog of template function in CPP to be able to use the same scenario for all types of parameters from data dictionary.
The example of mapping in the data dictionary is described here. Once the characteristics are defined you can read and write the described parameter using the functions mbc_master_get_parameter, mbc_master_set_parameter.
It is selection of user how to store the data and how to save it but the API provides the methods to read/write data over modbus and store them as instructed.
mb_parameter_descriptor_t device_parameters[] = {
{ CID_HOLD_U16_AB, STR("U16_AB"), STR("--"), MB_DEVICE_ADDR1, MB_PARAM_HOLDING,
HOLD_REG_START(holding_u16_ab), HOLD_REG_SIZE(holding_u16_ab),
0, PARAM_TYPE_U16_AB, (HOLD_REG_SIZE(holding_u16_ab) << 1),
OPTS( 0, USHRT_MAX, 0 ), PAR_PERMS_READ_WRITE_TRIGGER },
...
}
...
uint16_t my_data = 0;
...
esp_err_t err = mbc_master_set_parameter(CID_HOLD_U16_AB, "U16_AB", (uint8_t *)&my_data, &type);
if (err == ESP_OK) {
ESP_LOGI(TAG, "Set parameter data successfully.");
} else {
ESP_LOGE(TAG, "Set data fail, err = 0x%x (%s).", (int)err, (char*)esp_err_to_name(err));
}assign the value to test_v and then I bring test_v into my business logic. There seems to be some problems and it doesn't feel optimal.
The temp_data_ptr in this case gets the pointer to parameter instance in the parameter structure void *temp_data_ptr = master_get_param_data(param_descriptor); ).
Th example with the parameters stored in data structures and the code saves the data to the appropriate field of the structure as defined in data dictionary.
...
#pragma pack(push, 1)
typedef struct
{
#if CONFIG_FMB_EXT_TYPE_SUPPORT
uint16_t holding_u16_ab[2];
uint16_t holding_u16_ba[2];
} holding_reg_params_t;
#pragma pack(pop)
...
// This structure keeps the values that can be accessed from Modbus master
holding_reg_params_t holding_reg_params = { 0 };
....
mb_parameter_descriptor_t device_parameters[] = {
{ CID_HOLD_U16_AB, STR("U16_AB"), STR("--"), MB_DEVICE_ADDR1, MB_PARAM_HOLDING,
HOLD_REG_START(holding_u16_ab), HOLD_REG_SIZE(holding_u16_ab),
HOLD_OFFSET(holding_u16_ab), PARAM_TYPE_U16_AB, (HOLD_REG_SIZE(holding_u16_ab) << 1),
OPTS( 0, USHRT_MAX, 0 ), PAR_PERMS_READ_WRITE_TRIGGER },
...
}
const mb_parameter_descriptor_t* param_descriptor = NULL;
...
esp_err_t err = mbc_master_get_cid_info(cid, ¶m_descriptor); // get characteristic descriptor from data dictionary
...
void *temp_data_ptr = master_get_param_data(param_descriptor); // <<<< gets the pointer to the parameter instance as defined by offset HOLD_OFFSET(holding_u16_ab) in data dictionary.
...
// Send the data of the parameter stored in the holding_reg_params.holding_u16_ab to the slave.
esp_err_t err = mbc_master_set_parameter(CID_HOLD_U16_AB, "U16_AB", (uint8_t *)temp_data_ptr, &type);
if (err == ESP_OK) {
ESP_LOGI(TAG, "Set parameter data successfully.");
} else {
ESP_LOGE(TAG, "Set data fail, err = 0x%x (%s).", (int)err, (char*)esp_err_to_name(err));
}
yel-best
Hi My Friend.
1. I am currently doing modbus connection with some PLC devices. I need to see some detailed logs. For example, the sent message "01 03 A0 80 00 01 A7 E2" and then the received message "01 03 02 03 E8 B8 FA", I need to print to the console for output,I have been searching for a long time but I have not found how to open this part of the log.
2. In addition, the example does not seem to explain how to convert the value. For example, I have a float & u16 type value. How should I extract it for subsequent logic? I now use a very stupid way to do it, and I will *(uint16_t ) temp_data_ptr** for forced conversion, do you have any other suggestions?
I assign the value to
test_vand then I bring test_v into my business logic. There seems to be some problems and it doesn't feel optimal.