ComputerBoards CIO-DAS801, Manual

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Table 1-1. I/O Addresses
SERIAL PORT 3F8-3FF EGA 2B0-2BF
FLOPPY DISK 3F0-3F7 PARALLEL PRINTER 270-27F
SERIAL PORT 3E8-3EF ALT BUS MOUSE 23C-23F
CGA 3D0-3DF BUS MOUSE 238-23B
EGA 3C0-3CF EXPANSION UNIT (XT) 210-21F
PARALLEL PRINTER 3BC-3BF GAME CONTROL 200-20F
MDA 3B0-3BB HARD DISK (AT) 1F0-1FF
SDLC 3A0-3AF 80287 NUMERIC CO-P (AT) 0F0-0FF
SDLC 380-38F 8237 #2 (AT) 0C0-0DF
PARALLEL PRINTER 378-37F NMI MASK (XT) 0A0-0AF
HARD DISK (XT) 320-32F 8259 PIC #2 (AT) 0A0-0A1
PROTOTYPE CARD 310-31F DMA PAGE REGISTERS 080-08F
PROTOTYPE CARD 300-30F
CMOS RAM & NMI MASK (AT)
070-071
SERIAL PORT 2F8-2FF 8742 CONTROLLER (AT) 060-064
SERIAL PORT 2E8-2EF 8255 PPI (XT) 060-063
GPIB (AT) 2E0-2E7 8253 TIMER 040-043
EGA 2D0-2DF 8259 PIC #1 020-021
EGA 2C0-2CF 8237 DMA #1 000-00F
FUNCTION HEX
RANGE
FUNCTION HEX
RANGE
1.3.2 DIFFERENTIAL / SINGLE ENDED SELECT
The CIO-DAS80# has differential analog inputs. Differential inputs are 3-wire analog hookups consisting of a signal high, signal low
and chassis ground. The benefits of differential inputs are the ability to reject noise which affects both signal high and low, and the
ability to compensate for ground loops or potentials between signal low and chassis ground.
Although differential inputs are often preferable to single ended inputs, there are occasions when the floating nature of a differential
input can confound attempts to make a reading. In those cases, the CIO-DAS80# inputs can be converted to single-ended or modified
differential.
The CIO-EXP16 and CIO-EXP32 were designed to interface to a single-ended input. Failure to set the switches to single ended when
an EXP is connected will result in floating, unstable readings from the
EXP.
The analog inputs of the CIO-DAS80# may be set up as single ended or
differential. There are two ways to select between them.
The first method of selecting between the single ended and differential
inputs is with a set of eight switches located near the connector and
labeled 0-7 in white lettering on the board. In the down (off) position,
the input associated with that switch is in differential mode. In the up
(on) position the input is single-ended.
Figure 1-2 shows one analog input and the single-ended / differential
switch.
Figure 1-2. Input Configuration Switch
2