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Appendix C
Sample Programs
© National Instruments Corporation
C-17
GPIB-1014 User Manual
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| Summary:
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- Called to send device-dependent (data) messages
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when the GPIB-1014 is Controller-In-Charge
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(DSEND is called when the interface is Idle
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Controller)
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| Assumptions on entry:
| - GPIB-1014 is CIC
| - One Listener is addressed and its address is placed
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in the variable ola
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- The data to be sent is placed in datbuf
| - The variable datct contains the number of bytes to
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send
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| Actions:
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- Set up cmdbuf and cmdct and call CMD to address
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the GPIB-1014 as Talker, to address the Listener,
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and to unaddress all other devices
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- Go to standby and unassert ATN
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- Transfer the contents of datct to the d0 register
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- Load a0 register with the address of datbuf
| - Call DSEND to write the data
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- When the last byte has been sent, take control
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- Call CMD to unaddress all devices
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| Status on return:
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- The GPIB-1014 is Active Controller
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- All GPIB devices are unaddressed
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