Re: 6502 stack register at reset

From: Gerrit Heitsch <*gerrit_at_laosinh.s.bawue.de*> Date: Sat, 25 Nov 2017 21:58:54 +0100 Message-ID: <2daa2953-5b07-fee6-f108-a14e141c4f75@laosinh.s.bawue.de> · gerrit_at_laosinh.s.bawue.de

On 11/25/2017 09:53 PM, smf wrote:
> On 25/11/2017 20:34, silverdr@wfmh.org.pl wrote:
> 
>> Yup - I even remember wondering why.. long time ago. That's until I 
>> read somewhere that the SP is not initialised on H/W reset. 
> 
> Initialising registers costs money & you might not want the values that 
> the designers pick anyway.
> 
> However you'll probably see similar values each time you turn the 
> computer on, like you see similar patterns in ram.

Yes, but that can depend on the mask or even the batch and is not 
uniform. So don't count on it.

Ok, with DRAM it is and only depends on the manufacturer, but with SRAM 
and everything else using flipflops it's not.

  Gerrit

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