Instructions

87
7.7 GEN Protocol (GEN series communication language)
NOTE:
The address (ADR n) command must return an ”OK” response before any other commands are accepted.
7.7.1 Data Format
Serial data format is 8 bit, one start bit and one stop bit. No parity bit.
7.7.2 End of Message
The end of message is the Carriage Return character (ASCII 13, 0x0D). The power supply ignores
the Line Feed (ASCII 10, 0x0A) character.
7.7.3 Command Repeat
The backslash character ”\” will cause the last command to be repeated.
7.7.4 Checksum
The user may optionally add a checksum to the end of the command. The checksum is ”$” followed
by two hex characters. If a command or a query has checksum, the response will also have one.
There is no CR between the command string and the ”$” sign. Example: STT?$3A STAT?$7B
7.7.5 Acknowledge
The power supply acknowledges received commands by returning ”OK” message. If an error is
detected, the power supply will return an error message. The rules for checksum also apply to
the acknowledge feature.
7.7.6 Backspace
The backspace character (ASCII 8) clears the last character sent to the power supply.
7.7.7 Error Messages
The power supply will return error messages for illegal commands and illegal programming
parameters. Refer to Table 7-3 for programming error messages and Table 7-4 for command error
messages.
Fig.7-8: Serial link cable with RJ-45 shielded connectors (P/N: Z/RJ45)
#1
#2
#3
RS232/485
RS485
RS485
RS485
RS485
120 OHM
#31
8
1
1
8
L=0.5m typ.
8 PIN CONNECTOR (IN) 8 PIN CONNECTOR (OUT)
PIN NO. NAME PIN NO. NAME
HOUSING SHIELD HOUSING SHIELD
1 SG 1 SG
6 TXD- 6 RXD-
3 TXD+ 3 RXD+
5 RXD- 5 TXD-
4 RXD+ 4 TXD+
NOTES:
It is recommended when using ten or more power supplies in Daisy-chain system to connect
120Ω resistive termination at the last unit’s RS-485 out connector
120Ω, 0.5W between TXD+ and TXD-.
120Ω, 0.5W between RXD+ and RXD-.