Amplifier Research 75A250A, Руководство пользователя

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Model 75A250A Manual Text
2-6
REV A
2.2.2 Remote Operation (continued)
2.2.2.6 IEEE-488 Communications (continued)
Table 2-2
Remote Error Codes/Messages
IEEE-488 Serial Poll Model 75A250A Error Condition RS-232
Response (STB) Error
(binary/decimal) Message
(01000001) 65 BPM FAULT E1
(01000010) 66 THERMAL FAULT E2
(01000011) 68 INTERLOCK FAULT E3
(01000100) 72 PS1 FAULT E4
2.2.2.7 RS-232 Communications
If the RS-232 interface is active, the Model 75A250A will test for a properly connected RS-232
interface when it is switched into the remote operation mode. In order for the Model 75A250A to
recognize an RS-232 connection, the “Data Carrier Detect” (DCD) line must be asserted. This
line is sampled continuously to determine if the RS-232 connection is broken; therefore, it must
remain asserted in order for the RS-232 interface to function. The “Clear To Send” (CTS) line is
also used to gate information from the Model 75A250A. This line must be asserted in order to
receive information from the Model 75A250A. The CTS line can be used as a “handshake” line
to inform the Model 75A250A when it is permissible to send information. If the CTS line is de-
asserted in the middle of a transmission, the character in the process of being transmitted will be
completed and further transmission will halt until the CTS line is re-asserted. The
Model 75A250A itself asserts two lines: “Data Terminal Ready” (DTR) and “Request To Send”
(RTS). The DTR line is continuously asserted, while the RTS line is used to gate information into
the Model 75A250A. Connector pin-out information is given in
Table 2-3 .