EEC ESD-140, Руководство по эксплуатации

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7. Bus Remote Interface
RS-232 Interface
The RS-232 cabling should be configured as follows for a 9-pin serial port interface:
The COM port should have the following configuration:
19200 baud
8 data bits
1 stop bit
No parity
This interface does not support XON/XOFF protocol or any hardware handshaking.
The controller should be configured to ignore the handshaking lines DTR (pin 4), DSR
(pin 6) CTS (pin 8) and RTS (pin 7). If the port cannot be configured through software
to ignore these lines the handshake lines should be jumpered together in two different
sets. Pins 4 and 6 should be jumpered together and pins 7 and 8 should be jumpered
together at the controller end of the cable.
Sending Data
Once a command is sent to the instrument over the RS-232 bus the instrument will
send one of two responses. If the transfer was recognized and completed the
instrument will return with 06 hex or 6 decimal, the Acknowledge (ACK) ASCII control
code. If there is an error with the command string that is sent, the instrument will
respond with 15 hex or 21 decimal, the Not Acknowledge (NAK) ASCII control code.
The ACK or NAK response allows for software handshaking to monitor and control
data flow.
Receiving Data
When requesting data from the instrument it will automatically send the data back to
the controller input buffer. The controller input buffer will accumulate data being sent
from the instrument, including the ACK and NAK response strings, until it has been
read by the controller.
RS-232 Interface Command List
The RS-232 bus will automatically send any response back to the controller's input
buffer. Note that the commands are case sensitive and must be typed in capital letters.
Each command string should be terminated by the ASCII control code, New Line
<NL>, or OAh.
The following conventions are used to describe the commands syntax for the Ground
Instrument RS-232 Port PC / Bus Controller
2
3
5
2
3
5
TD
RD
TD
RD
SIG
GND
SIG
GND