hase@netmbx.UUCP (Hartmut Semken) (10/18/89)
In article <CMM.0.88.624463452.cmm1@cunixa.cc.columbia.edu> cmm1@CUNIXA.CC.COLUMBIA.EDU (Christopher M Mauritz) writes: >PC Ditto v3.01 will NOT work with TOS 1.4. I forget what the error >says, but I think it was something like: "Does not work with this >version of TOS" or something to that effect. Too bad there isn't a way >to piggy back the two versions of ROMs and have a hardware switch >between them. No? Well, the first solution it is easy, if You have a machine with TOS in 6 ROMs. These are xx256 JEDEC-pinout-compatible mask ROMs. So 27256 EPROMS are possible replacements. And so are 27512. Pin 1 of the 27256 is called Vpp (programming voltage) and is to be held at +5Volts when the ROM is simply used (not programmed). Pin 1 of the 27512 EPROMs is the necessary additional adress line. So, get Your EPROM programmer, read in each of Your original ROMs (all twelve of them), get 12 sockets (28 pin, 600 mil EPROM sockets), a 10 kOhms resistor, a siple litte switch, some isolated wire and 6 27512 (or C512) EPROMs. Remove pin 1 of 6 of Your sockets; this is done to isolate EPROM pin 1 from the ST circurit board. Plug in the remaining 6 sockets. See how pin 1 has lost contact to the +5Volts line. Connect all pin 1 with some wire. Now connect the 1 kOhms resistor to pin 1 and pin 28 of one of the upper sockets. Pin 28 is the +5Volts (Vcc) power source for the ROMs. Connect the wire to the switch and the switch to ground (pin 14 of the ROMs is ground, for example). Now the switch switches the most significant adress line for the 512-EPROMs between ground (low) and open (10-k pullup to Vcc; high). So the switch selects "upper half" or "lower half" of the EPROM. Burn a set of EPROMS with TOS 1.2 (or 1.0) in one half and Rainbow TOS in the other. works fine for me :-) Second solution: use 6 static RAMs (62256 or Nec42256 and a battery to emulate 6 ROMs. This was done by some german freak, who published his solution in the german magazine c't. The pcb is availeble, as are the required PAL chips. This even adds a Mega-ST-compatible clock to non-Megas... I'm still trying to find some time to get it to work... :-( hase -- Hartmut Semken, Lupsteiner Weg 67, 1000 Berlin 37 hase@netmbx.UUCP Dennis had stepped up into the top seat whet its founder had died of a lethal overdose of brick wall, taken while under the influence of a Ferrari and a bottle of tequila. (Douglas Adams; the long dark teatime...)
lawrence@techpub1.iscs.com (Lawrence Kelley) (10/19/89)
In article <3619@netmbx.UUCP> hase@netmbx.UUCP (Hartmut Semken) writes: >In article <CMM.0.88.624463452.cmm1@cunixa.cc.columbia.edu> cmm1@CUNIXA.CC.COLUMBIA.EDU (Christopher M Mauritz) writes: >>PC Ditto v3.01 will NOT work with TOS 1.4. I forget what the error >>says, but I think it was something like: "Does not work with this >>version of TOS" or something to that effect. Too bad there isn't a way >>to piggy back the two versions of ROMs and have a hardware switch >>between them. > Really? A friend of mine has both TOS 1.4 and PC Ditto v3.01 and Ditto runs with no problems. He has a 520ST with an EZ-RAM upgrade to 1 Meg.
andreas@nixpbe.uucp (10/23/89)
/* Written 3:32 pm Oct 19, 1989 by lawrence@techpub1.UUCP in nixpbe:comp.sys.atari.st */ /* ---------- "Re: Piggiback ROMs (2 TOS versions " ---------- */ In article <3619@netmbx.UUCP> hase@netmbx.UUCP (Hartmut Semken) writes: >In article <CMM.0.88.624463452.cmm1@cunixa.cc.columbia.edu> cmm1@CUNIXA.CC.COLUMBIA.EDU (Christopher M Mauritz) writes: >>PC Ditto v3.01 will NOT work with TOS 1.4. I forget what the error >>says, but I think it was something like: "Does not work with this >>version of TOS" or something to that effect. Too bad there isn't a way >>to piggy back the two versions of ROMs and have a hardware switch >>between them. > ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ Of course there is a way to switch between two version of TOS ! Use 27512 instead of 27256 and copy the first version from 0000 to 7fff and the second from 8000 to ffff. Now you can switch the two versions by connecting the upper adress line A15 (Pin 1 ?!) of all EPROMS to VCC or ground. It works fine ! CU :-) Andreas
Bob_BobR_Retelle@cup.portal.com (10/28/89)
> Of course there is a way to switch between two version of TOS ! > Use 27512 instead of 27256 and copy the first version from > 0000 to 7fff and the second from 8000 to ffff. Now you can > switch the two versions by connecting the upper adress line > A15 (Pin 1 ?!) of all EPROMS to VCC or ground. > It works fine ! Right... How many ComputerLand or BusinessLand customers are going to sit through this kind of bullshit and still walk out the door with your product..? Does the figure %00.00.00001 have any meaning...? Atari Corp. is still in the minor leagues as far as truly credible computer
R_Tim_Coslet@cup.portal.com (10/29/89)
> >> Of course there is a way to switch between two version of TOS ! > >Right... > >How many ComputerLand or BusinessLand customers are going to sit through >this kind of bullshit and still walk out the door with your product..? > >Does the figure %00.00.00001 have any meaning...? > >Atari Corp. is still in the minor leagues as far as truly credible computer Hmm... if breaking alot of old software with a new OS release makes Atari a "minor league" computer company... what is DEC with their release of VAX VMS 5.0 (followed quickly by 5.0-1 then 5.1 then 5.1-1). VAX VMS 5 broke so much software (even some DEC things, not just 3rd party stuff) that it was impossible to use for an awful long time where I work. Just because an OS upgrade breaks things doesn't say the company isn't doing a good job (of course with DEC it was easier to get fixed upgrades to the broken software, but if I was paying thousands of dollars per application program... I would expect INSTANT bug fixes too). R. Tim Coslet Usenet: R_Tim_Coslet@cup.portal.com BIX: r.tim_coslet