[coreboot] Holding the s2895 in reset powers off the machine

Carl-Daniel Hailfinger c-d.hailfinger.devel.2006 at gmx.net
Wed Jul 8 02:17:35 CEST 2009

On 07.07.2009 23:03, Myles Watson wrote:
>> Just for my interest, but why does someone need to power on a system while
>> holding the reset button?
> In this case it is to allow my FPGA time to initialize (or for me to
> reprogram it) before the Opteron tries to set up HyperTransport
> communication with it.

I have no idea if the reset button directly triggers a reset line or
something similar on the processor, but it would be interesting to know:
1. Does the power off also happen if you hold reset after the machine
has already been booted? (Do n seconds of reset always trigger a poweroff?)
2. Which part of the board reacts to the held reset line and triggers
the poweroff?
3. Is reset maybe somehow coupled to PWRGOOD and holding down reset is
perceived as electrical problem of the power supply?



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