Digital I/O (HMX)
Overview⚓︎
The HMX-specific Digital I/Os are listed below. Check the technical file for more information about the different thresholds and whether it's possible to change state (digital out).
List of supported outputs⚓︎
There are four different types of digital outputs.
- outputs with ability to sink a signal to ground
- outputs with the ability to source VCC power (they have different maximum current), either controlled by software or always on.
- output with both an internal buzzer and the ability to connect an external buzzer.
| Hardware Name | Software Name | Software group | Connected to | Source Type |
|---|---|---|---|---|
| SINK_OUT_1 | OUT_SINK1 | gpiod | Sink | |
| SINK_OUT_2 | OUT_SINK2 | gpiod | Sink | |
| Digital_output_ETH2_ACT | ETH2_ACT | gpiod | Source (Special) | |
| SOURCE_Digital_OUT_1 | OUT_SOURCE1 | gpiod | Source (VCC power) | |
| SOURCE_Digital_OUT_2 | OUT_SOURCE2 | gpiod | Source (VCC power) | |
| SOURCE_OUT_3 | SOURCE_OUT_7 | Source (Always powered) | ||
| SOURCE_OUT_4 | pwr_out_active | gpio-leds | SOURCE_OUT_5, SOURCE_OUT_6 | Source (VCC power) |
| SOURCE_OUT_5 | pwr_out_active | gpio-leds | SOURCE_OUT_4, SOURCE_OUT_6 | Source (VCC power) |
| SOURCE_OUT_6 | pwr_out_active | gpio-leds | SOURCE_OUT_4, SOURCE_OUT_5 | Source (VCC power) |
| SOURCE_OUT_7 | SOURCE_OUT_3 | Source (Always powered) | ||
| SOURCE_OUT_8 | pwr_out_equipment | gpio-leds | Source (VCC power) | |
| SOURCE_PWR_OUT_LED_1 | pwr_out_led_1 | gpio-leds | Source (VCC power) | |
| SOURCE_PWR_OUT_LED_2 | pwr_out_led_2 | gpio-leds | Source (VCC power) | |
| SOURCE_PWR_OUT_BUZZER | pwr_out_buzzer | gpio-leds | Source (VCC power, Buzzer) |
Example usage:
#gpio-leds
echo 1 > /sys/class/leds/:pwr_out_led_1/brightness
#gpiod
gpioset $(gpiofind OUT_SINK1)=1
List of supported inputs⚓︎
There are two types of digital inputs with pull up or pull down resistor.
| Hardware Name | Software Name | Software group | Input Type |
|---|---|---|---|
| Digital_input_pulldown_1 | IN_PULLDOWN1 | gpiod | Pull-down (33k to GND) |
| Digital_input_pulldown_2 | IN_PULLDOWN2 | gpiod | Pull-down (33k to GND) |
| Digital_input_pullup_1 | IN_PULLUP1 | gpiod | Pull-up (33k to VCC) |
| Digital_input_pullup_2 | IN_PULLUP2 | gpiod | Pull-up (33k to VCC) |
| Digital_input_HMI_1 | IN_HMI1 | gpiod | Pull-up (33k to VCC) |
| Digital_input_HMI_2 | IN_HMI2 | gpiod | Pull-up (33k to VCC) |
Fault detection⚓︎
The unit has fault detection that goes high if a fault is detected(gpiod).
| Fault Name (software name) | Connected to |
|---|---|
| SINK_FAULT | SINK_OUT_1, SINK_OUT_2 |
| SOURCE_1_FAULT | SOURCE_Digital_OUT_1 |
| SOURCE_2_FAULT | SOURCE_Digital_OUT_2 |
| SOURCE_4_FAULT | SOURCE_OUT_4, SOURCE_OUT_5, SOURCE_OUT_6 |
| SOURCE_5_FAULT | SOURCE_PWR_OUT_BUZZER |
| SOURCE_6_FAULT | SOURCE_OUT_8 |
Sleep and wake up⚓︎
For Digital in, wake-up is enabled by default. If you want to disable this feature, one way is to modify the device tree when building the image, the other is to unbind the gpio-keys as follows.
After waking up, you can rebind if you want to use the gpio-keys.You can disable one or more wake-up sources using signal-specific macro codes.
| Hardware Name | Software Name | Key Code | Macro Code |
|---|---|---|---|
| Digital_input_start | in_start | 656 | KEY_MACRO1 |
| Digital_input_pulldown_1 | in_pulldown1 | 657 | KEY_MACRO2 |
| Digital_input_pulldown_2 | in_pulldown2 | 658 | KEY_MACRO3 |
| Digital_input_pullup_1 | in_pullup1 | 659 | KEY_MACRO4 |
| Digital_input_pullup_2 | in_pullup2 | 660 | KEY_MACRO5 |
| Digital_input_HMI_1 | in_hmi1 | 661 | KEY_MACRO6 |
| Digital_input_HMI_2 | in_hmi2 | 662 | KEY_MACRO7 |
Example on how to disable in_start (all start signals):
It is also possible, within limits, to see what caused the wake up. The following example displays all wakeup_count instances where gpio-keys is wakeup4 (wakeup4 has all digital in together so here you cannot see which signal was triggered).