(Ultimem) expansion RAM cleared on hard reset?
Moderator: Moderators
- pixel
- Vic 20 Scientist
- Posts: 1357
- Joined: Fri Feb 28, 2014 3:56 am
- Website: http://hugbox.org/
- Location: Berlin, Germany
- Occupation: Pan–galactic shaman
(Ultimem) expansion RAM cleared on hard reset?
My stuff's in storage, so I cannot check myself.
A man without talent or ambition is most easily pleased. Others set his path and he is content.
https://github.com/SvenMichaelKlose
https://github.com/SvenMichaelKlose
- Mike
- Herr VC
- Posts: 4841
- Joined: Wed Dec 01, 2004 1:57 pm
- Location: Munich, Germany
- Occupation: electrical engineer
Re: (Ultimem) expansion RAM cleared on hard reset?
Not on its own. I'd guess at least.
What happens in VICE is probably another matter. Ctrl-R performs a reset but keeps RAM contents - internal, normal RAM expansion, and presumably of banked RAM expansions as well -, Shift-Ctrl-R clears the RAM, better said, applies the RAM init pattern to BLK0..BLK3 but fills BLK5 with all zeroes.
On real hardware, you'd need a routine in firmware to clear the banked RAM, as the KERNAL of course knows nothing about Ultimem. Also, the KERNAL only initialises pages 0, 2 and 3 upon power on/reset and doesn't touch other RAM, i.e. the RAM test performed is non-destructive.
...
You're concerned the contents of a RAM disk on Ultimem (hopefully) survive a reset?
What happens in VICE is probably another matter. Ctrl-R performs a reset but keeps RAM contents - internal, normal RAM expansion, and presumably of banked RAM expansions as well -, Shift-Ctrl-R clears the RAM, better said, applies the RAM init pattern to BLK0..BLK3 but fills BLK5 with all zeroes.
On real hardware, you'd need a routine in firmware to clear the banked RAM, as the KERNAL of course knows nothing about Ultimem. Also, the KERNAL only initialises pages 0, 2 and 3 upon power on/reset and doesn't touch other RAM, i.e. the RAM test performed is non-destructive.
...
You're concerned the contents of a RAM disk on Ultimem (hopefully) survive a reset?
- pixel
- Vic 20 Scientist
- Posts: 1357
- Joined: Fri Feb 28, 2014 3:56 am
- Website: http://hugbox.org/
- Location: Berlin, Germany
- Occupation: Pan–galactic shaman
Re: (Ultimem) expansion RAM cleared on hard reset?
That would be lovely. And it's key to the fast restore on reset. Want "Ingle" to jump right back to where it was.Mike wrote:You're concerned the contents of a RAM disk on Ultimem (hopefully) survive a reset?
Cannot work on that game at the moment but wanna nail something down anyway. Am starting a new job next week, so even I should get an own place to live here in Berlin again.
A man without talent or ambition is most easily pleased. Others set his path and he is content.
https://github.com/SvenMichaelKlose
https://github.com/SvenMichaelKlose
- pixel
- Vic 20 Scientist
- Posts: 1357
- Joined: Fri Feb 28, 2014 3:56 am
- Website: http://hugbox.org/
- Location: Berlin, Germany
- Occupation: Pan–galactic shaman
Re: (Ultimem) expansion RAM cleared on hard reset?
Oh, well, and multi-processing. Not multi-tasking.
And thanks for your help, btw.
And thanks for your help, btw.
A man without talent or ambition is most easily pleased. Others set his path and he is content.
https://github.com/SvenMichaelKlose
https://github.com/SvenMichaelKlose
Re: (Ultimem) expansion RAM cleared on hard reset?
Sorry for the delay. RAM is not reset on reset.
Jim
Jim
- eslapion
- ultimate expander
- Posts: 5458
- Joined: Fri Jun 23, 2006 7:50 pm
- Location: Canada
- Occupation: 8bit addict
Re: (Ultimem) expansion RAM cleared on hard reset?
The RAM in 32k/35k Ultimate Expanders I have sold in the past is also not cleared on reset.
Some of them used Cypress SRAM ICs which had trickle power mode. If you had a 1541 disk drive attached to the IEC port, the trickle amount of power flowing back in the VIC-20 through the reset line would be enough to keep the content of the SRAM intact even when turning the VIC-20 off.
Some of them used Cypress SRAM ICs which had trickle power mode. If you had a 1541 disk drive attached to the IEC port, the trickle amount of power flowing back in the VIC-20 through the reset line would be enough to keep the content of the SRAM intact even when turning the VIC-20 off.
Be normal.
- pixel
- Vic 20 Scientist
- Posts: 1357
- Joined: Fri Feb 28, 2014 3:56 am
- Website: http://hugbox.org/
- Location: Berlin, Germany
- Occupation: Pan–galactic shaman
Re: (Ultimem) expansion RAM cleared on hard reset?
Hey, that's great! Thanks! Works out pretty well. Returns to the GUI within a blink of an eye. Will show off later.
A man without talent or ambition is most easily pleased. Others set his path and he is content.
https://github.com/SvenMichaelKlose
https://github.com/SvenMichaelKlose