Table of Contents
Advertisement
Register Map
before it is fed to the A/D converter. The L suffix cards can
take LOW input signals, 2.5 milli Volts full scale, and boost
them by a factor of up to 1000, ie 2.5 Volts full scale. Please
ensure that
jumper selected input range. L suffix cards, eg AD1211L have
gains of 1-10-100-1000. H suffix cards, eg AD1211H have gains
of 1-2-4-8.
Set By:
These bits are set under program control.
Reset By: They are cleared under program control.
These bits are automatically cleared at power up.
Note:
The AD1221 and AD1220 cards do NOT have
programmable gain and ADGCR bits 6 & 7 always
read back as zero.
ADGCR A/D Gain Selection.
Gain
Select1
Bit 7
0
0
1
1
Bits 4 & 5. Reserved For Future Expansion. Read / Write.
_________________________________________________ _
These two bits currently have no effect, and are thus
"don't care" bits. They should be written to as 0 to ensure
compatibility with future enhancements to the AD1200 range.
_______________________________________
Bits 0, 1, 2 & 3. Channel Select. Read / Write.
These four bits select the channel that is fed to the input of
Chapter 3
the boosted input voltage does not exceed the
_______________________
Figure 3-7. Gain Selection.
Gain
Select0
Bit 6
Hex
0
00
1
40
0
80
1
C0
AD1200 Reference
Gain Selected
AD12XXL
AD12XXH
1
10
100
1000
1
2
4
8
Page 59
Advertisement
Table of Contents
