From 1152189acba568550b7b3567ade683fa971b4962 Mon Sep 17 00:00:00 2001 From: Werner Almesberger Date: Wed, 7 Sep 2011 10:56:06 -0300 Subject: [PATCH] labsw/LOG: theory that the failures to switch are caused by EMI (on buttons) --- labsw/LOG | 15 +++++++++++++++ 1 file changed, 15 insertions(+) diff --git a/labsw/LOG b/labsw/LOG index 1389779..7c38112 100644 --- a/labsw/LOG +++ b/labsw/LOG @@ -195,6 +195,21 @@ Rework: - turn-on cycle: all LEDs green, no power (not a reset) - 5+ normal cycles +Further analysis: the absence of more abnormal states, such as LEDs +contradicting relays or LEDs just going dark suggests that the problem +is may not be USB data corruption. At least some of the symptoms would +be compatible with EMI from switching the relay creating false signals +on the buttons. + +The "all LEDs green" condition would be a false press of MAIN. The +CH2 green condition would be harder to explain. Maybe the MAIN LED +was also green and I didn't notice. In this case, it would have been +a combination of the MAIN and CH1 buttons (MAIN to exit remote mode, +turn off all the channels, and enable the channel buttons. Then CH1 to +turn on CH1 again.) + +To do: debounce buttons (in software) before accepting a state change. + --------------------- (next PCB run)