Amada CD-A Series, Руководство по эксплуатации

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APPENDIX D: COMMUNICATIONS
CD-A DUAL PULSE RESISTANCE WELDING POWER SUPPLY
D-2 990-430
Section II. Communications Protocol and Commands
Command Format
Each external command will be formatted as follows:
<stx> <cmd> <cnt> <data> <cksum> <etx>.
Definition of a Command:
<stx> 1 byte The data packet will start with a STX (start of text 0x02) character.
<cmd> 2 bytes This is a two character ASCII string denoting the command. (i.e. “TY”)
<cnt> 2 bytes This is a count of data bytes to follow, converted into a decimal ASCII
number. (“00” to “99”)
<data> n bytes This is ASCII numbers or ASCII data and may or may not be required
by the command. See the individual command.
Multiple byte ordering is: [MSB][…][LSB]
<cksum> 2 bytes This is a two charter ASCII HEX string calculated from the sum of all
bytes except <stx>, <cksum>, and <etx>. Then masked with 255 (0xFF)
<etx> 1 byte This terminates the transmission. (End of text 0x03)
The CD-A will respond with a Negative Acknowledge Command (“
NK ”) when an error is encountered
in response to a command. The format and reasons follow.
<stx>
“NK” <cnt> <err> <cksum> <etx>
Where <err> = ‘1’
‘2’
‘3’
NO<SOH>
BAD checksum
Unrecognized command ‘4’
‘5’
‘6’ Timeout
In Local
Data Bad
A valid command will return EITHER DATA OR
“AK” .
The <ACK> format is: <stx> “AK” <cnt> <data> <cksum> <etx>
The
DATA format is: <stx> <cmd> <cnt> <ascii data> <cksum> <etx>
When you issue a command to the CD-A, you need to wait for the response before you issue the next
command. This waiting period should be at least 250ms. The CD-A should respond within this timeout.
VARIABLE: italics.
RANGE OF PARAMETERS:
low_end - high_end (separated by hyphen).