who knows what happens on a warm boot????

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charles
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who knows what happens on a warm boot????

Post by charles »

hey prog'r-s :
would anybody like to take a stab at what happens once a program freezes and then we press the "warm reset" button on the backside of the st's.

does it entirly wipe out all memory?

i'm not looking for the simple answear : it resets ! but seem to recall reading somewhere that a cold reset clears the st ,memory entirerly... ,

and a warm reset just sets us back to the gem desktop......... leaving what ever it was in the "buffers or prosserors"to be cleared when the next program is exucuted.

so....has anyone ever formulated a program to retrieve the data a person was working on just before the computer freezes and we have to reset?

like an accessory that retains this info in a resevered area of memory ,then once re-booted finds this allocacted space ,and writes our
retrieved data to file..

to explain (or plea!) further a program like this would be very helpfull for some cubase users ,or art program users ,even text scrip-bers...that just have that certain ability to crash any program they use!

well deep in though !
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Post by Womble »

Certainly doesnt clear the memory - some demos had reset proof features. Sub Humans In Turkey for instance - no matter how long you held the warm reset button their splash screen was always there when you released it.
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Post by Mug UK »

Most reset routines were (esp. viruses) very resilient to warm boots.

First thing they did after attaching themselves to the disk read/write routines would be to put the magic number into the reset vector so that it would always be there after a warm start.
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Post by simonsunnyboy »

A reset is nothing else but a jump to a special subroutine, specified by the Reset vector. It does not alter memory or registers by default so it is up to this reset routine what to do next. This can be another demo screen, reinit of the OS (default) or a jump to a debugger.
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Re: who knows what happens on a warm boot????

Post by Nyh »

callaghan wrote:hey prog'r-s :
would anybody like to take a stab at what happens once a program freezes and then we press the "warm reset" button on the backside of the st's.

does it entirly wipe out all memory?
No it doesn't. I have retrieved some sourcecode from memory after the editor hanged. After the editor crashed I was very keen on retriving the data. I removed the harddisk from my ST and pressed the reset button and booted from floppy. I fired up bugaboo and searched the memory for some keywords. When found the data I dumped the memory blocks on disk and got my precsious source code back.
callaghan wrote:i'm not looking for the simple answear : it resets ! but seem to recall reading somewhere that a cold reset clears the st ,memory entirerly... ,

and a warm reset just sets us back to the gem desktop......... leaving what ever it was in the "buffers or prosserors"to be cleared when the next program is exucuted.
This happens after a reset:
1 test for diagnostic cardridge
2 init memory controller IF(LPEEK($420)==$752019F3 AND LPEEK($43A)==$237698AA) THEN POKE $FF8001,PEEK($424)
3 execute reset vector IF(LPEEK($426)=$31415926) THEN GOTO LPEEK($42A)
4 init soundchip, set video on 50 Hz, init colour display, set screenmemory at $10000
IF(warm boot) GOTO 8
5 determine RAM configuration
6 wipe RAM
7 init systemvariables for a correct warm boot

8 clear RAM from $93A to $FFF, init system variables, init interuptvectors, init BIOS
9 check and execute 'Bit 26' cartridge programs
10 init video mode
11 check and execute 'Bit 24' cartridge programs
12 CPU enable interrupts
13 check and execute 'Bit 25' cartridge programs
14 init GEMDOS
15 check and execute 'Bit 27' cartridge programs
16 try to boot from floppy
17 try to boot from harddisk
18 execute \AUTO\*.PRG
19 start AES
20 system is up and running
callaghan wrote:so....has anyone ever formulated a program to retrieve the data a person was working on just before the computer freezes and we have to reset?

like an accessory that retains this info in a resevered area of memory ,then once re-booted finds this allocacted space ,and writes our
retrieved data to file..
Yes, used bugaboo for this.
callaghan wrote:to explain (or plea!) further a program like this would be very helpfull for some cubase users ,or art program users ,even text scrip-bers...that just have that certain ability to crash any program they use!
You can do that if you know where you are looking for. Ripper cardridges are very good in retrieving data from memory too, but once again: you have to know where you are looking for. Anything else as text or pictures will be quite hard.

Hans Wessels
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Re: who knows what happens on a warm boot????

Post by ggn »

Nyh wrote:
callaghan wrote:hey prog'r-s :
would anybody like to take a stab at what happens once a program freezes and then we press the "warm reset" button on the backside of the st's.

does it entirly wipe out all memory?
No it doesn't. I have retrieved some sourcecode from memory after the editor hanged. After the editor crashed I was very keen on retriving the data. I removed the harddisk from my ST and pressed the reset button and booted from floppy. I fired up bugaboo and searched the memory for some keywords. When found the data I dumped the memory blocks on disk and got my precsious source code back.
Yay! Another bugaboo user :)

George
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Post by gwEm »

exactlty what nyh said - great summary!

but be aware the warm reset does also resets some peripherial chips, for example the MFP, DMA, etc. if doing reset proof stuff you may need to reinitialise these chips yourself.
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Post by prog99 »

Some coders might just about remember a reset resident version of devpac? Certainly helped when that tricky bit of code crashed and you'd never saved it...
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