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2.4.6 A/D Gain Control Register
(WRITE) Base+9 : A/D Gain Control Register Format
y
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
X X X X X GAIN2
GAIN1
GAIN0
The
A-812PG provides gain factor of 1/2/4/8/16.
The gain control register controls the gain
of A/D input signal. JP4 A/D input selection will effect the gain factor.
NOTE :
If gain control code changed, the hardware need to delay extra gain
settling time.
The gain settling time is different for different gain control code.
The
software driver does not take care the gain settling time, so the user need to delay the
gain settling time if gain changed.
If the application program need to run in different
machines, the user need to implement a machine independent timer.
A-812PG GAIN CONTROL CODE TABLE
JP4 = 5V
Settling Time GAIN Input Range GAIN2 GAIN1 GAIN0
23 us
1
+/- 5V
0
0
0
23 us
2
+/- 2.5V
0
0
1
25 us
4
+/- 1.25V
0
1
0
28 us
8
+/- 0.625V
0
1
1
28 us
16
+/- 0.3125V 1
0
0
JP4 = 10V
Settling Time GAIN Input Range GAIN2 GAIN1 GAIN0
23 us
1
+/- 10V
0
0
0
23 us
2
+/- 5V
0
0
1
25 us
4
+/- 2.5V
0
1
0
28 us
8
+/- 1. 25V
0
1
1
28 us
16
+/- 0.625V
1
0
0
A-812PG Hardware Manual (Ver.1.2, Sep/2005, IPH-004-12) -----
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