Z-World Fox LP3500 User Manual page 60

unsigned int anaInDriver(unsigned int cmd,
unsigned int len);
Reads the voltage of an analog input channel by serial-clocking an 8-bit command to the ADS7870
device by its Direct Mode method. The conversion begins as soon as the last data bit is transferred.
An exception error will occur if Direct Mode bit D7 is not set.
PARAMETER
cmd contains a gain code and a channel code as follows.
D7—1; D6–D4—Gain Code; D3–D0—Channel Code
Use the following calculation and the tables below to determine cmd:
cmd = 0x80 | (gain_code*16) + channel_code
Channel Code
0
1
2
3
4
5
6
7
* Negative input is ground.
len, the output bit length, is always 12 bits.
54
Gain Code Multiplier
0 1
1 2
2 4
3 5
4 8
5 10
6 16
7 20
Differential
Channel Code
Input Lines
+AIN0 -AIN1 8
+AIN2 -AIN3 9
+AIN4 -AIN5 10
+AIN6 -AIN7 11
Reserved 12
Reserved 13
Reserved 14
Reserved 15
Voltage
Range
0–20 V
0–10 V
0–5 V
0–4 V
0–2.5 V
0–2 V
0–1.25 V
0–1 V
Single-Ended
4–20 mA
*
Lines
Input Lines
AIN0 AIN0
AIN1 AIN1
AIN2 AIN2
AIN3 AIN3
AIN4 Reserved
AIN5 Reserved
AIN6 Reserved
AIN7 Reserved
Fox (LP3500)