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modbus_read_bits(3)
===================
NAME
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modbus_read_bits - read many bits
SYNOPSIS
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*int modbus_read_bits(modbus_t *'ctx', int 'addr', int 'nb', uint8_t *'dest');*
DESCRIPTION
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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 function shall return the number of read bits if successful. Otherwise it
shall return -1 and set errno.
ERRORS
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*EMBMDATA*::
Too many bits requested
SEE ALSO
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linkmb:modbus_write_bit[3]
linkmb:modbus_write_bits[3]
AUTHORS
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The libmodbus documentation was written by Stéphane Raimbault
<stephane.raimbault@gmail.com>