Programming instructions

(8) Information
cl
10s
q
PIG
8 BIT
Analog
ANALOG 4
Input
TO-
DIGITAL
CONVERTER
Figure 13 - High-speed analog-to-digital converter programming logic
A program sequence to sample a function at the input to the converter,
and store the result in memory register 10 would be:
PROGRAM SEQUENCE
/analog-to-digital converter
W /location of sampled result
421
SCi
/places sample in AC
dac 10
/deposit result
LOW SPEED ANALOG-TO-DIGITAL CONVERTER
(TYPICAL INPUT DEVICE)
An analog-to-digital converter with a resolution of 12 bits and a conversion
time of 60 microseconds can be connected to PDP-4. The converter is given
an iot command to sample the analog function, and in 60 microseconds the
converter will contain a 12-bit number proportional to the input. At the
completion of the sample, the converter flag is set to a 1, signifying that
the input data is ready.
The contents of the converter buffer are read into the AC with a program
command. The action which transfers the information from the converter
to the AC also resets the converter flag. An iot skip instruction is used which
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