Rockwell Automation 1775-S5_SR5,D17756.5.5 User Manual PLC-3 FAMILY I/0 User Manual

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Binary Command Language

Appendix A

A-26

If the success response code returns, the next byte contains the number of
words in the reference block which do not match the block in memory.
The following response block shows a successful verify block command:

STX

OSC

SIZ

RSP

ETX

CHK

DAT

The data byte stores the miscomparison count. If any other response code
returns, no data follows.

Uploading/Downloading

You can read from and write to physical locations in processor memory
using the read block physical and write block physical commands. These
commands are executed faster than read block and write block commands.
However, physical addresses change when you edit the program, which
makes it difficult to keep track of where a given word or block of data is
stored. Therefore, use the read block physical and write block physical
commands only for uploading and downloading the entire memory
contents to/from a computer.

The read block physical and write block physical commands use physical
addresses which are different than the addressing used for other BCL
commands. The address requires two words (four bytes) with the least
significant byte sent first. The most significant byte must contain the value
01 hex. The value contained in the other bytes ranges from 0 to the highest
address in the processor programmable processor (depending on the
amount of memory in the system). We explain these two commands in the
following 4 subsections.

Read Block Physical

Hex: 07

Parameters: Physical address of the first word in the block, number of
words in the block

Description: The following command block uses a read block physical
command to read 16 words starting with word 66120 (10248 hex):

STX

ISC

SIZ

CMD

CHK

DAT

ETX