USB-I/O Interface Adapter GPIO-24. Programmer's Reference Manual.
7.9. GPIO_GET_ADC_CHANNEL_CFG (0x26)
The GPIO_GET_ADC_VAL command retrieves current voltage from two channels at once.
GPIO_GET_ADC_VAL Command
| Byte 0 | GPIO_GET_ADC_VAL | Response ID (0x11). |
| Byte 1 | ECHO | Echo to associate command with the response. |
| Byte 2 | CHANNEL1 | ID number of the ADC channel |
| Byte 3 | CHANNEL2 | ID number of the ADC channel |
| Bytes 4..7 | Reserved | Reserved (must be 0). |
Command is an 8-byte array of the following format:
- Byte 0: GPIO_GET_ADC_VAL (0x11)
This byte contains command ID (command type). It should be set to 0x11.
- Byte 1: ECHO
This byte is used to associate a response received from GPIO-24 adapter with a specific command. Response will contain exactly the same value in its echo byte.
- Bytes 2..3: CHANNEL1/CHANNEL2
The GPIO-24 adapter can retrieve current voltage from two channels at once. These bytes define the ID number of the ADC channel to retrieve voltage from:
0 – C.1 pin;
1 – C.2 pin;
2 – C.5 pin;
3 – C.6 pin;
4 – B.3 pin.
- Bytes 4..7: Reserved
These bytes are reserved for future usage and must be set to 0.
For convenience GPIO_GET_ADC_VAL_CMD structure is declared in reports.h file.
GPIO-24 adapter sends GPIO_GET_ADC_VAL response after command execution. Current voltage is specified inside the response.
GPIO_GET_ADC_VAL Response
| Byte 0 | GPIO_GET_ADC_VAL | Response ID (0x11). |
| Byte 1 | ECHO | Echo to associate a command with the response. |
| Byte 2 | ST | Command execution status |
| Byte 3 | CHANNEL1_LSB | Current voltage on the ADC channel (least significant byte) |
| Byte 4 | CHANNEL1_MSB | Current voltage on the ADC channel (most significant byte) |
| Byte 5 | CHANNEL2_LSB | Current voltage on the ADC channel (least significant byte) |
| Byte 6 | CHANNEL2_MSB | Current voltage on the ADC channel (most significant byte) |
| Byte 7 | Reserved | Reserved |
Response is an 8-byte array of the following format:
- Byte 0: GPIO_GET_ADC_VAL (0x11)
This byte contains response ID (response type). This byte will contain 0x26.
- Byte 1: ECHO
This byte is used to associate a response received from GPIO-24 adapter with a specific command. Response will contain exactly the same value in its echo byte.
- Byte 2: ST
- Byte 3: CHANNEL1_LSB/CHANNEL1_MSB
Current voltage on the ADC channel
Byte 3: CHANNEL1_LSB – least significant byte of current voltage.
Byte 4: CHANNEL1_MSB – most significant byte of current voltage.
- Byte 5: CHANNEL2_LSB
Current voltage on the ADC channel
Byte 5: CHANNEL2_LSB – least significant byte of current voltage.
Byte 6: CHANNEL2_MSB – most significant byte of current voltage.
- Byte 7: Reserved
This byte is reserved for future usage.
For convenience GPIO_GET_ADC_VAL_RSP structure is declared in reports.h file.
