Service Requests - Motorola R-2001A Service Manual

22-43. The format of the error message is:
The two digit number nn defines the error condition as listed in table 22-5. The carriage return (CR) and line
feed (LF) characters are the termination sequence used by analyzer whenever it transmitts information. All
characters are ASC II coded.
Error Code
00
01
02
03
04
05
06
07
08
09
10
22-44. To effectively utilize the error message capability of the analyzer it is necessary to address the unit as a
talker after the transmission of each command string. The bus controller must then be programmed to
recognize the error message and to decode the error number. A successful data transmission wilt send back an
error code 00 when addressed as a talker. The controller should be programmed to ignore error 00 and to
display any other error to the operator. Of course if a valid output command followed by the trigger command
was sent, the talker address will result in the requested data being output to the controller.
22-45. Service Requests. There are only two conditions that will cause the analyzer to generate a service
request (SRQ) on the bus. IfaSRQ is generated it must be cleared by a serial poll of the analyzer. The serial poll
is a bus command which results in a data byte being sent to the controller from the analyzer. The data byte
indicates the cause of the SRQ. Table 22-6 lists the SRQ causes and the corresponding serial poll data.
Condition
Depressing Cursor
Down Key
RF load over
Temperature
ERROR nn (CR)(LF)
Table 22-5. Error Messages
Condition
Data requested without trigger
Involid mnemonic prefix
One character mnemonic (not T)
Invalid mnemonic suffix
Exponent overflow
Data underflow
Data overflow
Data transmitted, not allowed
Invalid data
RF input power exceeded
Level or mod control error
Table 22-6. SRQ Data
Binary
01000001
01000010
22-10
Return Data
HEX DEC
41
42
65
66