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- 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
- --------
- linkmb:modbus_write_bit[3]
- linkmb:modbus_write_bits[3]
- AUTHORS
- -------
- The libmodbus documentation was written by Stéphane Raimbault
- <stephane.raimbault@gmail.com>
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