LizardLad_1
Posts: 126
Joined: Sat Jan 13, 2018 12:29 am

How to tell what addresses are MMIO and what addresses are RAM

Mon Jan 29, 2018 6:48 am

Hello, How would I be able to tell what addresses are MMIO. Is there a range of addresses that are MMIO? or are they just scattered?

bzt
Posts: 206
Joined: Sat Oct 14, 2017 9:57 pm

Re: How to tell what addresses are MMIO and what addresses are RAM

Mon Jan 29, 2018 10:27 am

For old Raspberry, it's 0x20000000, for newer boards 0x3F000000. Everything below is conventional RAM. There's no such thing as E820. For the true limit of RAM (as in usable by the CPU, since the CPU/GPU split can be configured in config.txt), you have to make a MessageBox call.

bzt

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