"Igor" wrote in message news:xn0djpsie59fgi000@powernews.libero.it... : Reading past messages I've understood that AppleII+ roms are not pin : compatible with eprom chips. Is that true also for Apple IIe/IIc/IIgs : roms? : If not, what kind of eproms should I use to back up or substitute them? I know that IIe in the US are 2764 for CD and EF, 2716 for Video ROM and KeyBoard ROM, but the Euro models are 2732 for Video ROM as they are dual- language. The Platinum //e has CF rom which would be 27128. The ROM-FF or original IIc ROM is 27128, and ROM00 through ROM04 take 27256. I assume that Video and Keyboard ROMs follow the IIe US standard since they weren't marketed in other countries. The IIgs I am not sure about, I've heard they are eprom compatible from one source and not compatible from other sources, so I won't claim either now. Bill @ GarberStreet Enterprizez };-) Web Site - http://garberstreet.netfirms.com Email - willy46pa @ comcast DOT net Change DOT to a dot to contact me --- This email ain't infected, dude! Checked by AVG anti-virus system (http://www.grisoft.com). Version: 6.0.699 / Virus Database: 456 - Release Date: 6/4/04 "Bill Garber" wrote in message news:SvadnZVbwNX1D0ndRVn_iw@comcast.com... : : "Igor" wrote in message : news:xn0djpsie59fgi000@powernews.libero.it... : : Reading past messages I've understood that AppleII+ roms are : not pin : : compatible with eprom chips. Is that true also for Apple : IIe/IIc/IIgs : : roms? : : If not, what kind of eproms should I use to back up or : substitute them? : : I know that IIe in the US are 2764 for CD and EF, : 2716 for Video ROM and KeyBoard ROM, but the Euro : models are 2732 for Video ROM as they are dual- : language. The Platinum //e has CF rom which would : be 27128. : : The ROM-FF or original IIc ROM is 27128, and ROM00 : through ROM04 take 27256. I assume that Video and : Keyboard ROMs follow the IIe US standard since they : weren't marketed in other countries. : : The IIgs I am not sure about, I've heard they are : eprom compatible from one source and not compatible : from other sources, so I won't claim either now. Some II/II+ info to help with the adapter. The II/II+ ROMs have 3 chip selects: 18 = CS2 20 = /CS1 21 = /CS3 The 2716 has the following: 18 = /CE 20 = /OE 21 = Vpp (+5v for READ, +25v for program) Jim Sather shows a design for an adapter: Apple II -> 2716 18 -> 21 20 -> 20+18 21 -> n/c I have an outline somewhere and also I began a schematic for making these. You'll mostly just want to mod the F8 rom, I think. Bill @ GarberStreet Enterprizez };-) Web Site - http://garberstreet.netfirms.com Email - willy46pa @ comcast DOT net Change DOT to a dot to contact me --- This email ain't infected, dude! Checked by AVG anti-virus system (http://www.grisoft.com). Version: 6.0.699 / Virus Database: 456 - Release Date: 6/4/04 "Bill Garber" wrote in message news:SvadnZVbwNX1D0ndRVn_iw@comcast.com... : : "Igor" wrote in message : news:xn0djpsie59fgi000@powernews.libero.it... : : Reading past messages I've understood that AppleII+ roms are : not pin : : compatible with eprom chips. Is that true also for Apple : IIe/IIc/IIgs : : roms? : : If not, what kind of eproms should I use to back up or : substitute them? : : I know that IIe in the US are 2764 for CD and EF, : 2716 for Video ROM and KeyBoard ROM, but the Euro : models are 2732 for Video ROM as they are dual- : language. The Platinum //e has CF rom which would : be 27128. Correction: The Video ROMs in IIe are 2732 for US, and 2764 for the Euro. Sorry 'bout that. :o) : The ROM-FF or original IIc ROM is 27128, and ROM00 : through ROM04 take 27256. I assume that Video and : Keyboard ROMs follow the IIe US standard since they : weren't marketed in other countries. : : The IIgs I am not sure about, I've heard they are : eprom compatible from one source and not compatible : from other sources, so I won't claim either now. : : Bill @ GarberStreet Enterprizez };-) : Web Site - http://garberstreet.netfirms.com : Email - willy46pa @ comcast DOT net : Change DOT to a dot to contact me : : : : --- : This email ain't infected, dude! : : Checked by AVG anti-virus system (http://www.grisoft.com). : Version: 6.0.699 / Virus Database: 456 - Release Date: 6/4/04 : --- This email ain't infected, dude! Checked by AVG anti-virus system (http://www.grisoft.com). Version: 6.0.699 / Virus Database: 456 - Release Date: 6/4/04 Igor wrote: > Reading past messages I've understood that AppleII+ roms are not pin > compatible with eprom chips. Is that true also for Apple IIe/IIc/IIgs > roms? > If not, what kind of eproms should I use to back up or substitute them? The IIe and IIc can use regular EPROMs. 2732,2764 or 27128 I don't recall on the ROM 1 but the ROM 3 IIgs can use regular EPROMs. If you really need the size I can dig out a ROM 3 that came with EPROMs and check the size The II+ ROMs aren't pin caompatible but you can easily make an adapter to use 2716 EPROMs. From Understanding The Apple II 1. se two 24 pin DIP sockets/If pin 1 is not clearly marked on the sockets, choose pin 1 and mark it with fingernail polish or other permanent marking. 2. All pictured wiring is shown in phantom. Pins are bent inward and wiring is routed on inside of sockets. Use 30 gauge insulated wire and keep wire lengths as short as possible. 3. Remove pin 21 from lower socket. Save this pin as a spare. 4. Bend pins 18 and 21 of the upper socket inward so they will not make contact with the lower socket when the sockets are mated. This must be done carefully so the EPROM will still make contact with the bent pins when it is inserted into the upper socket. 5. Solder a short jumper between bent pin 18 and the base of pin 20 in the upper socket. Carefully dress the jumper at the base of pin 20 so it will not interfere with the mating of the two sockets. 6. Solder a short jumper between bent pin 21 on the upper socket and the base of pin 18 on the lower socket. Carefully dress the jumper on the base of pin 18 so it will not interfere with plugging the completed adapter into the ROM socket. 7. Push the upper socket into the lower socket. Inspect visually or with an ohmmeter to make certain there is no contact between pins 18 on the upper and lower socket. With some sockets it may be necessary to modify or insulate pin 18 on the lower socket so that it does not touch pin 18 on the upper socket. This must be done carefully so pin 18 is still firmly mounted in the lower socket. Api of the adapter http://www3.telus.net/waynes/adapter.jpg Wayne "Igor" writes: >Reading past messages I've understood that AppleII+ roms are not pin >compatible with eprom chips. Is that true also for Apple IIe/IIc/IIgs >roms? >If not, what kind of eproms should I use to back up or substitute them? ROM EPROM pins Apple II & II+ Integer/Applesoft/Monitor 2316B none 24 Rev 0-6 Text ROM 2513 none 24 Rev 7 and RFI Text ROM 2316B 2716 24 Apple IIe and IIc Keyboard ROM 2316B 2716 24 NTSC Video ROM 2332B 2732 24 Canadian Video ROM 2364A 68764 24 PAL Video ROM 2364B 2764 28 IIe CD & EF 2364B 2764 28 IIe CF 23128 27128 28 IIc original 23128 27128 28 IIc 3.5/memx/IIc+ 23256 27256 28 Apple IIgs ROM00/01/03 1 megabit ??? none 28 Note that the 2316B has 3 chip enable inputs whose active level can be specified by the purchaser. Apple chose levels that were not compatible with the 2716 /CE /OE and Vpp inputs for the Apple II. With the Rev 7 Text ROM they used a 2716 compatible set of chip enables. The IIgs uses a 28 pin 1 MegaBit (128KB) ROM but the equivalent EPROM has 32 pins... -- David Wilson School of IT & CS, Uni of Wollongong, Australia David Wilson writes: >Apple IIgs >ROM00/01/03 1 megabit ??? none 28 >The IIgs uses a 28 pin 1 MegaBit (128KB) ROM but the >equivalent EPROM has 32 pins... I just double checked the ROM03 schematics, my memory data book and my ROM03 PCB. 1) The PCB is laid out for 32 pin sockets (but my IIgs has only got 28 pin sockets soldered to it). 2) There are two versions of 128Kx8 EPROMs. One has /OE on pin 24 and is not usable in the IIgs. The other has A16 on pin 24 and /OE is on pin 2. Compatible EPROMs are: Hitachi HN27C301G Toshiba TC571001D So if your ROM03 has 32 pin sockets you can use EPROMs. -- David Wilson School of IT & CS, Uni of Wollongong, Australia Igor schrieb: > My eprom burner can't burn eproms greater than 2764 (it's an AP-64) so > at the moment I can't copy IIgs roms but I'm sure that I'll be able to > find the images somewhere if I'll ever need. Get a 27256 pinout and locate A13 and A14. Connect these pins to a DIP switch so you can apply +5V or 0V to them. Now you can treat a 27128 as two 2764 (one with A13 low, one with A14 high). A 27256 is equal to four 2764. Many 27128 and nearly all 27256 require a programming voltage (Vpp) of 12,5V instead of 21V. To change Vpp, connect a 12V zener diode from Pin 1 of the EPROM socket to ground (the cathode ring points towards Pin 1). You don't need this modification if vou just want to read out the ROMs. Patrick In Igor wrote: > Patrick Schaefer wrote: > >> >> Get a 27256 pinout and locate A13 and A14. Connect these pins to a >> DIP switch so you can apply +5V or 0V to them. Now you can treat a >> 27128 as two 2764 (one with A13 low, one with A14 high). A 27256 is >> equal to four 2764. > > it's interesting, but how do I tell the burning program that I'm using > an eprom greater then 8kbyte? When I start up I'm asked for what eprom > I want to use, 2716, 2732 or 2764. I'm almost sure that the program > uses that information to know how much it has to read, 2, 4 or 8k. A 2764 EPROM has 13 address lines numbered A0 through A12. A 27128 has one extra address line (A13). Your EPROM programmer only controls the A0 to A12. If you plug in a 27128 and pull A13 low by connecting it to 0V you can read and write the first half of it by just pretending it's a 2764. Now connect A13 to +5V and you can use the upper half of the EPROM. -- Roger Johnstone, Invercargill, New Zealand http://vintageware.orcon.net.nz/ ________________________________________________________________________ No Silicon Heaven? Preposterous! Where would all the calculators go? Kryten, from the Red Dwarf episode "The Last Day" "Quadrajet1" wrote in message news:20040622043308.10778.00000309@mb-m25.aol.com... : >I thought i'd ask these guestions due to the recent discussion thread on : >eproms and roms on the apple // and //e etc : > : >I have an exotic product called the "moustrap" chip....for the //e ..it was : >made (briefly till apple sued them) by a : >company that took a switchable ROM (ie. able to hold the old pre-mousetext : >char set and also the new mousetext char set) on the same EPROM chip and : >switch back and forth between char sets... : >and it was all incased in a hard plastic with a nice little label called : >"mousetrap" w/date (shinny metal foil label whoo who) with a cable off the : >end of it and a toggle switch...so back in the day..(1983 or so) : : I made a number of them mods back in the day, : right after the enhanced //e came out. Never : got sued since I didn't commercialize it, but : probably made 40-50 sets total. If all you made was 40-50 sets, then you didn't even put a dent in Apple's revenue, they shouldn't care. :o) : But what I did was take the 3 ROMs and switch : from regular //e and enhanced //e. The 2 ROMs : and the video ROM got switched. It was so simple : with an EPROM burner. Take a 27128 and burn the : lower half of CD ROM with regular //e code and the : upper half with enhanced //e. Same with EF ROM and : the Video ROM, except it used a smaller EPROM. : Obviously a 65C02 was installed. : : All that was needed was to toggle 1 pin high or : low on each ROM to switch back and forth. Tie : all three pins together, all done with 1 wire. : You would have to reboot once you switched over : of course. The easiest way to acomplish this would be to burn 2 eproms, one with the old video ROM and one with the newer enhanced video ROM, pull up the /OE pins stack them and solder them one to the other and add a switch between the /OE pins. Push them in the socket and mount the switch. Another is to burn a double sized eprom and switch the highest address line between +5v and gnd. So, in the case of a 2716, you would burn the 2 ROMs in each half of a 2732 and switch the A11 line on pin 21 from high to low for upper half and lower half. You can also run A11 to AN2 and use softswitches to select the upper and lower half of the eprom. Bill @ GarberStreet Enterprizez };-) Web Site - http://garberstreet.netfirms.com Email - willy46pa @ comcast DOT net Change DOT to a dot to contact me --- This email ain't infected, dude! Checked by AVG anti-virus system (http://www.grisoft.com). Version: 6.0.699 / Virus Database: 456 - Release Date: 6/7/04