MTX -3G-JAVA series User Manual page 58


A/D conversion
In order to read samples from the ADC buffer, you have to send three bytes over the I2C bus before
sending the I2C STOP condition
1. Address byte (write mode): 0x90 hexadecimal
2. Control byte:
a. 0x00 hexadecimal to read from ADC1
b. 0x01 hexadecimal to read from ADC2
3. Address byte (read mode): 0x91 hexadecimal
4. Dummy byte 1: 0x00 hexadecimal
5. Dummy byte 2: 0x10 hexadecimal
After that you should have three bytes in the I2C read buffer: the second one is the 8‐bit sample
value retrieved from the AD converter, in straight binary format.
You can calculate the voltage value from the A/D input using the following expression:
where V is the voltage value present at the A/D converter input (0 ≤ V
ADC
sample value in decimal format (0 ≤ D ≤ 255)
www.mtx‐terminals.com
3
256
www.mtxm2m.com
MTX M2M® by MATRIX ELECTRONICA S.L.U
MTX‐3G‐JAVA Family
≤ 2988.3mV) and D is the
ADC
2015/10 v1.6
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