On 23 abr, 19:58, Jamie
t wrote:
Look on the board that has the micro for some electro caps. I work with
those types of CPU's and what I have done for a synchronized start up
is to employ a delay circuit for the CPU, a sort of power management
process. Check the caps to make all are up to snuff.. A low valued
cap is going the allow the CPU to start sooner in the power management
section. If this is a new problem, either the main unit is taking too
long, indicating a hardware problem or you do have something strange
going on. You may want to check for bad caps and solder joints, a very
common problem. Especially with today's Lead Free solders.

Jamie

Thank you.
There are two electrolytics, one in parallell with 5V supply and
another after a 47 ohm resistor to supply the IR sensor. There are
some resistors to power the leds and buttons and I see no other
components that could be used for a delay.

This micro is connected to a VFD driver chip to show the time, channel
number, etc to a VFD display. While starting it shows some moving
dashes on the 7-segment part, then the text "on" and then reboots. If
it doesn't reboot then shows "Init" and the last channel number. There
is no visible difference in the moving dashes between a good and a
failed initialization but when it starts fine, the "on" text keeps
slightly longer on the display, around 1 additional second, being all
the signals it receives from the main unit the same. This additional
one second is what makes the difference.