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MODBUS_READ_BITS(3)            Libmodbus Manual            MODBUS_READ_BITS(3)

NAME
       modbus_read_bits - read many bits

SYNOPSIS
       int modbus_read_bits(modbus_t *ctx, int addr, int nb, uint8_t *dest);

DESCRIPTION
       The modbus_read_bits() 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 or
       FALSE.

       You must take care to allocate enough memory to store the results in
       dest (at least nb * sizeof(uint8_t)).

       The function uses the Modbus function code 0x01 (read coil status).

RETURN VALUE
       The modbus_read_bits() function shall return the number of read bits if
       successful. Otherwise it shall return -1 and set errno.

ERRORS
       EMBMDATA
           Too many bits requested

SEE ALSO
       modbus_write_bit(3) modbus_write_bits(3)

AUTHORS
       The libmodbus documentation was written by Stephane Raimbault
       <stephane.raimbault@gmail.com[1]>

NOTES
        1. stephane.raimbault@gmail.com
           mailto:stephane.raimbault@gmail.com

libmodbus 3.1.0                   10/06/2013               MODBUS_READ_BITS(3)