Features & operation

The latest revision of ATXRaspi (R3) allows you to configure various functional and behavior parameters. You may use ATXRaspi with momentary buttons (R1+) or latching switches (R2.7+).

Momentary button operation

By default the board is configured to work with a momentary button and works this way:

  • To turn ON the Pi all you have to do is press the power button.
  • To REBOOT the Pi hold the button pressed at least ~2s.  The SHUTDOWN signal pulses shortly and the Pi (via shutdowncheck.sh script) will detect this pulse and start a reboot sequence. The status LED blinks for up to 1 minute while waiting for the reboot to complete (and BOOTOK signal to become HIGH again).
  • To SHUTDOWN the Pi you have to press the button and release shortly (200ms+) and release it quickly. The SHUTDOWN signal goes HIGH and the Pi goes into shutdown sequence. While shutdown is in progress the button (aka status) LED will pulse slowly. When shutdown is complete (BOOTOK goes LOW), the status LED pulses faster and ATXRaspi cuts power off to the Pi after a few more seconds.
  • To FORCE-OFF power – hold the button pressed for about ~6 seconds to cutoff power regardless of any other conditions. This may be handy when the Pi is in an unknown state or is locked up/frozen.

Latching button operation

  • To turn ON the Pi all you have to do is press the button or flip the power switch. Since it’s a latching button/switch it will retain its position until switched back or pressed again to unlatch.
  • Although REBOOT makes less sense with a latching switch, this function is supported and possible even with a latching switch. You can issue a reboot by quickly depressing the button/switch to the OFF position and then re-pressing it to the ON position. The SHUTDOWN signal pulses shortly and the Pi (via shutdowncheck.sh script) will detect this pulse and start a reboot sequence. The status LED blinks for up to 1 minute while waiting for the reboot to complete (and BOOTOK signal to become HIGH again).
  • To SHUTDOWN the Pi simply depress the power button/switch to the OFF position. After ~2s the SHUTDOWN signal goes HIGH and the Pi goes into shutdown sequence. While shutdown is in progress the button (aka status) LED will pulse slowly. When shutdown is complete (BOOTOK goes LOW), the status LED pulses faster and ATXRaspi cuts power off to the Pi after a few more seconds.
  • To FORCE-OFF – assuming BOOTOK is LOW – depress the power button/switch to OFF position, after ~6s the power will be cutoff to the Pi. If the BOOTOK is HIGH, normal shutdown occurs, but if the BOOTOK does not go LOW as expected after ~1m, power is cutoff to the Pi.

Other modes of operation (R3 only)

ATXRaspi R3 introduced the use of solder jumpers that can be cut open or soldered closed to change some behavior. Here are the available jumpers:

When ATXRaspi R3 is first powered up, you will notice 3 sequences of RED LED blinks, separated by 0.5s delays. These blinks indicate the state of the settings below, in the following order:

  • Latching-BTN
    • Open (default, 1 blink) – this implies you are using a momentary switch/button (non-latching)
    • Closed (2 blinks) – solder this jumper closed to use a latching switch (ie toggle button or similar)
  • Reset-Enable
    • Closed (default, 1 blink) – reboot is enabled
    • Open (2 blinks) – cut this jumper open to disable the reboot function
  • Short-Press-Shutdown (ignored when Latching-BTN jumper is closed)
    • Closed (default, 1 blink) – short press triggers shutdown, long press triggers reboot
    • Open (2 blinks) – You may cut this jumper open to invert the reboot/shutdown delays (short-press triggers a reboot, long press triggers shutdown – this was the default behavior up until R2.8)
      • ​Errata for Short-Press-Reboot/Long-Press-Shutdown (2 blinks) – instead of cutting the jumper – it requires a 1K resistor soldered from this jumper or from LED+ to 5V (from input 5V) to activate this mode – this will be fixed in next release. Example how this can be achieved in the meantime:

It’s possible to completely power off your Pi from the command line, see this page for details.

The ATXRaspi forum is a good place to share projects and see what others have done. Here’s a nice example of how a user integrated ATXRaspi in a home media center.