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Description of commands
Single letter commands
Command D
It is important to understand the sequence of operation on the IEEE bus when a data
read-back command is executed. When the ‘D’ Command is sent it prepares the 9814 to
transmit (i.e. act as a talker). The controller program must then execute an ‘INPUT’
statement to actually initiate the data transfer. The data must be terminated with the cor-
rect character to complete the transfer.
Invalid terminating characters cause the IEEE bus to hang.
The terminator is controller dependent and the 9814 allows either CR or LF to be used,
as determined by the 9814 Command T1 or T2. Note that the T1 or T2 command
(terminating setting) must be done before the ‘D’ command is executed.
When the 9814 is in the over-range condition the front panel display shows 1….. but this
is not transmitted on read-back. The character string ‘OVERRNG’ is sent. In all other
cases the read-back is exactly as seen on the display.
EXAMPLE: ( HP BASIC )
10 REMOTE 708
20 OUTPUT 708;"T2" !SET TERMINATOR
30 OUTPUT 708;"D" !TRANSMIT DISPLAY
40 ENTER 708;A$ !READ RETURNED VALUE IN
50 PRINT A$ !PRINT IT
Command H
Sets output to full scale.
EXAMPLE: ( CBM BASIC )
10 OPEN 1,7 :REM OPEN 9814 ADDRESS 7
20 PRINT # 1,'H' :REM SET OUTPUT TO F. SCALE
30 END :REM END
Command I
Sets the 9814 to generate a serial poll request for service by the bus controller should
an ‘OP ERROR’ arise. ( Auto-cal units only )
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