From 14039d54a011b7dec9c4fea9207de59ab6350784 Mon Sep 17 00:00:00 2001 From: Mark van Renswoude Date: Sun, 16 Apr 2017 13:21:59 +0200 Subject: [PATCH] Added some build notes of my struggles --- Pi/PiPower.py | 2 -- Pi/notes.txt | 19 ++++++++++++++++++- 2 files changed, 18 insertions(+), 3 deletions(-) diff --git a/Pi/PiPower.py b/Pi/PiPower.py index 3ca4aa3..d9cbb16 100644 --- a/Pi/PiPower.py +++ b/Pi/PiPower.py @@ -11,7 +11,6 @@ import time import os GPIO.setmode(GPIO.BCM) -GPIO.setup(15, GPIO.OUT) GPIO.setup(18, GPIO.IN, pull_up_down=GPIO.PUD_DOWN) hasShutdown = False @@ -24,7 +23,6 @@ def shutdownSignal(channel): GPIO.add_event_detect(18, GPIO.RISING, callback=shutdownSignal, bouncetime=300) -GPIO.output(15, GPIO.HIGH) try: diff --git a/Pi/notes.txt b/Pi/notes.txt index ae322fb..b30c958 100644 --- a/Pi/notes.txt +++ b/Pi/notes.txt @@ -33,4 +33,21 @@ enable_uart=1 I have encountered this default of 0 in RetroPie, but I've seen reports for a standard installation as well: -https://www.raspberrypi.org/forums/viewtopic.php?f=28&t=141195 \ No newline at end of file +https://www.raspberrypi.org/forums/viewtopic.php?f=28&t=141195 + + + + + +You can connect power directly to PP1 or PP2 (+5V) and PP5 (GND). + +Add some capacitors between de ATTiny85's +5V and GND pins. +I learned the hard way that if you don't, the power will drop to the +ATTiny and it'll reboot as soon as the Pi draws power, taking the +relay and thus the Pi with it. This cycle repeated and killed my Pi. + +I bodged it and added in order two 100 nF ceramic capacitors, one 10 uF +electrolytic and one 470 uF electrolytic to get stable results. +I'm still learning electronics basics, but I recognize this is bad design. +Maybe a diode would've helped to prevent the Pi from draining the +capacitors immediately? \ No newline at end of file