Download Model GPIB-MAC User Manual

November 1985
0 National Instruments
The interpretation of each device’s response, other than
the RQS bit, is device specific. For example, the polled
device might set a particular bit in the response byte to
indicate that it has data to transfer, and another bit to
indicate a need for reprogramming. Consult the device
documentation for interpretation of the response byte.
Each device’s serial poll response byte is returned as a
numeric string giving the decimal value of the byte,
followed by <CR> and <LF>. If a device does not
respond in the timeout period, the GPIB-MAC returns
string -1 and records the EABO error. The time limit is
set to l/l0 second unless you called tmo to change it.
Each response corresponds directly to an address you
specify, therefore, there are exactly as many lines of
responses, including - 1, as the number of addresses you
specify.
If you call rsp and the GPIB-MAC is not CIC, it
attempts to become CIC. If it cannot become CIC, it
records the ECIC error. Refer to Appendix B for more
information.
If this is the first function you caIl that requires GPIB
controller capability, and you have not disabled System
Controller capability with rsc, the GPIB-MAC sends
Interface Clear @FC) to make itself CIC. It also asserts
Remote Enable.
If you passed control to some other GPIB device,
control must be passed back to you or you must send
IFC to make yourself CIC before making this call.
Otherwise, the ECIC error will be posted.
If you call rsp without an argument, the GPIB-MAC
records the EARG error.
Refer also to tmo for timeout information.
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SECTION FOUR - FUNCTIONS