"The analogue interface card offers the Acorn system user
laboratory standard facilities for the examination and control of analogue
signals. It is a 100mm x 160mm Eurocard and connects to the standard Acorn bus
using a 64 way indirect connector.
The following devices are used:
DAC1222
(2 off) 12 bit Digital to Analogue converters, fully buffered with
BlFET OP AMPS, giving output voltages in the range —5.12V to +5.11V a resolution
of 2.5mv.
ADC1210
12 bit Analogue to Digital converter, with eight channel analogue
multiplexer and sample and hold circuit. Input voltage range —5.12V to +5.11V,
resolution 2.5mV.
LH0071
Precision voltage reference (10.24V) removing any need for range
adjustment or calibration on the ADC or the DAC's.
6522
Versatile Interface Adaptor. Controls the ADC enabling software
programmable conversion rate using internal timers and full interrupt control of
the analogue system.
The board also has single bit digital input and output
signals, enabling a storage oscilloscope or X - Y recorder to be driven directly
by the analogue outputs, using the digital output for the z axis (beam on/off or
pen down/up) and the input for interrupt control.
ADC conversion rates:
12 bit up to 10,000 conversion/sec
8/10 bit up to 25,000 conversion/sec
Connections
8 analogue inputs ) -5.12V
2 analogue outputs ) to +5.11V
Digital input
) TTL
Digital input/output
) level
10.24V reference output
All interleaved with reference ground lines.
Schematics:
Documentation:
Photos:
None
Data Sheets