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Can I write to multiple holding registers? #88
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@per1234 is that something that would be a good addition to the library? If so, I can implement it with something like this: /*Take in a set of matching addresses and values those addresses to be set to */
int ModbusServer::holdingRegistersWrite(int addresses[], uint16_t values[], size_t length)
{
if(sizeof(addresses/addresses[0]) || sizeof(values/values[0]) != length)
{
return -1;
}
for(size_t element = 0; element < length; element++)
{
if (_mbMapping.start_registers > addresses[element] ||
(_mbMapping.start_registers + _mbMapping.nb_registers) < (addresses[element] + 1))
{
errno = EMBXILADD;
return 0;
}
}
for(element = 0; element < length; element++)
{
_mbMapping.tab_registers[addresses[element] - _mbMapping.start_registers] = values[element];
}
return 1;
} |
For the master/client, the write multiple registers function is supported by using
Note if memory is constrained, this can cause high memory usage due to a dynamic memory allocation to hold the register values, and large local variables in the |
In
ModbusServer.h
andModbusClient.h
I only see holdingRegisterWrite (write to a single register). Does the interface support an action for multiple writes, likewriteHoldingRegisters
? I know that the Modbus protocol does support this.The text was updated successfully, but these errors were encountered: