modbus_mask_write_register - mask a single register

       Martijn de Gouw <martijn.de.gouw@prodrive.nl> The libmodbus documentation was written by Stéphane
       Raimbault <stephane.raimbault@gmail.com>

libmodbus v3.1.6                                   12/09/2019                            MODBUS_MASK_WRITE_RE(3)

       The modbus_mask_write_register() function shall modify the value of the holding register at the address
       addr of the remote device using the algorithm:

           new value = (current value AND 'and') OR ('or' AND (NOT 'and'))

       The function uses the Modbus function code 0x16 (mask single register).

       modbus_mask_write_register - mask a single register

       The function shall return 1 if successful. Otherwise it shall return -1 and set errno.

modbus_read_registers(3) modbus_write_registers(3)

intmodbus_mask_write_register(modbus_t*ctx,intaddr,uint16_tand,uint16_tor);