RTC

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ravi
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RTC

Post by ravi »

Hello Octocontrabass

if i read and write elkhart lake RTC register with assembly in and out instruction (0x70 and 0x71)

RDC, 614109- chapter 27.2

but i if do it with mmio(FD00000h + 70h/71h) i am not able to do it. i am using the same procedure as we do with in and out instruction

thanks
Ravi
Octocontrabass
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Re: RTC

Post by Octocontrabass »

That looks like a copy/paste error in the datasheet. You can't use MMIO to access the RTC.
tito
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Joined: Wed Jul 03, 2024 3:31 am

Re: RTC

Post by tito »

Hello Ravi,

i still get no valid values (most 0) reading RTC of Elkhart Lake using
asm out/in 70h/71h

and there is no entry in the windows device manager, where the resource is described.

So, i think, i must use mmio FD00000h + 70h/71h as descrbed in the Intel Document Number: 636722 Chap 26.2.

i am stil confused about this chapter. Is port io still supported?

do you got it working for Elkhart Lake? with which tech (pio or mmio)?

thank you
Tito
ravi
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Re: RTC

Post by ravi »

Yes TiTo

I think MMIO didnot work

RTC works with 0x70/0x71.. in/out instructions
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