A3000 startup procedure?

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dgrubb
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A3000 startup procedure?

Post by dgrubb » Fri Jun 08, 2018 5:53 pm

In the ARM2 datasheet it notes that coming out of reset the PC goes to 0x0 (RAM in the A3000 memory map) and starts loading code from there. Meanwhile, the start of ROM is mapped up at 0x3400000.

How does the A3000 startup and get to a place where it can begin executing RISC OS?

Phlamethrower
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Re: A3000 startup procedure?

Post by Phlamethrower » Fri Jun 08, 2018 6:16 pm

On reset, MEMC maps the ROM to &00000000. The ROM code then performs a magic handshake to restore it to normal behaviour.

(See section 5.4 of the MEMC manual - http://www.home.marutan.net/arcemdocs/)

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dgrubb
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Re: A3000 startup procedure?

Post by dgrubb » Fri Jun 08, 2018 6:33 pm

Phlamethrower wrote:
Fri Jun 08, 2018 6:16 pm
On reset, MEMC maps the ROM to &00000000. The ROM code then performs a magic handshake to restore it to normal behaviour.

(See section 5.4 of the MEMC manual - http://www.home.marutan.net/arcemdocs/)
Got it. Thanks for the reference.

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