The number of a data block
The address of the first byte in the block.
The number of bytes to read.
The function returns 0 on success. Nonzero return codes may be passed to daveStrerror() to get a textual explanation of what happened. Generally, positive error codes represent errors reported by the PLC, while negative ones represent errors detected by LIBNODAVE, e.g. no response from the PLC.
Reads a sequence of bytes from PLC memory.