Analog Inputs. More...
Defines | |
| #define | ANALOG_MAX 1023 |
| Maximum value for an analog reading. | |
Functions | |
| uint16_t | analog_read (uint8_t port) |
The Happyboard has 16 analog inputs. They are used for sensors such as gyroscopes, distance sensors, IR phototransistor/LED pairs, and third-party sensors. In JoyOS, the distance sensors and gyros have their own library code; do not use analog_read() with these sensors. These inputs are fed into a 10 Bit ADC. The ADC communicates with the main processor via SPI, and can do so at 500kHz (20k samples per second.) In reality the actual maximum sample rate is slightly lower due to overheads in the OS code. (Also, the bottleneck analog input sampling is usually processing code, rather than the actual data acquisition).
The analog, digital, and encoder inputs (as well as the LCD) are run off a separate 5V regulated supply. This supply can supply up to 400mA to power the input sensors.
| uint16_t analog_read | ( | uint8_t | port | ) |
Read an analog port value.
| port | port number to read (8..23). |