modbus_read_bits - read many bits
int modbus_read_bits(modbus_t *ctx, int
addr , int nb, uint8_t
function shall read the status of the nb
bits (coils) to the address addr
of the remote device. The result of
reading is stored in dest
array as unsigned bytes (8 bits) set to TRUE
You must take care to allocate enough memory to store the results in dest
(at least nb
The function uses the Modbus function code 0x01 (read coil status).
The function shall return the number of read bits if successful. Otherwise it
shall return -1 and set errno.
Too many bits requested
The libmodbus documentation was written by Stéphane Raimbault