8k. HN61364 = 8k A15 is connected to a chip select to enable/disable the whole chip (really just output enable not chip enable despite the /CEx labels), and the actual address lines are only A0-A12
It's mostly like 27C64 but with 3 OE lines, customer programmable to be either active high or low as part of the mask programming. Although the schematic labels them as /CE0 /CE1 /CE2, really they are all OE not CE, and it appears that /CE1 should be shown as active-high, so really: /OE0, OE1, /OE2 , and /CS is a normal actual whole chip enable, active low. I was just now in the middle of drawing up an adapter for that chip like FlexROM_102 but for that chip, to facilitate using the main rom replacement feature of REX Classic in a 200 the way I have already for 100 and 102. But it may be simpler to make a different kind of adapter that replaces both chips with a single larger chip on a single adapter in the main rom socket and simply remove the 8k chip. The /BANK1 line goes to both chips the same, and A15 ends up activating one or the other exclusively at any given moment. bkw On Sun, Nov 13, 2022, 4:48 PM Mike Stein <[email protected]> wrote: > Looking at the schematic, are you sure it's 8K and not 16 (27x128)? > > Looks standard except for pins 26 & 27 > > On Sun, Nov 13, 2022 at 4:23 PM Stephen Adolph <[email protected]> > wrote: > >> Georg, >> What type of ROM chips did you use, when you replaced your ROMs with >> patched versions? >> I've been pondering what the simplest way to do that is. >> The 8K M13 socket is wired oddly, and doesnt seem compatible with a 27C64. >> thx >> Steve >> >> On Sun, Nov 13, 2022 at 12:30 PM Georg Käter < >> [email protected]> wrote: >> >>> Hello together, >>> >>> >>> >>> I own a M200 "German/EU Version" (Art.Nr. 26-3860H) w/modem, for German >>> market it was delivered with set of keyboard >>> >>> caps and a data tape including driver for keyboard and printer. I tried >>> this in VirtualT and it seems to work so far. To run REX >>> >>> on my M200 I replaced original ROM by ROM from VirtualT patched to serve >>> german keyboard mapping. >>> >>> For your reference I´ve added original ROM files and files from tape for >>> your reference. >>> >>> >>> >>> Regards >>> >>> Georg >>> >>> >>> Georg Käter >>> Gangolfsweg 44 >>> D-52076 Aachen >>> Tel. : +49 2408 7194987 >>> Fax. : +49 2408 7196758 >>> Mobil : +49 171 4839954 >>> E-Mail : >>> [email protected] >>> >>> ========== Ihre Nachricht ========================================== >>> >>> *von* : Cedric Amand <[email protected]> >>> *gesendet* : Sonntag, 13. November 2022, 15:37 >>> *an* : [email protected] >>> *Betreff* : [M100] custom key mapping generator for Tandy 200 >>> >>> __________ Originalnachricht _______________________________________ >>> >>> My point exactly Brian ! >>> How did they come up with that idea ? It makes no sense. It really >>> prevents you from using the option rom socket. >>> The docs does not talk about removing it. >>> >>> And even if you could remove it ; the installation procedure of that ROM >>> is not easy at all, requires to type two "calls" with the freaking keyboard >>> inverted. >>> OK - us nerds 40 years later can do it easily, just type "CQLL", but >>> imagine explaining that to a random journalist in 1984 ?! >>> Especially as the french doc (which I happen to have) says to type >>> "CALL" not CQLL. >>> >>> I also wonder if other markets are affected by this plague, >>> If anyone here lives in germany and owns a qwertz (or other keyboard >>> variant) of the M200 : do you have a "stock option ROM" as well ? >>> >>> I also wish to thank Stephen publicly for the time he invested into >>> helping me, as indeed, you can't use an option ROM (and even less a REX#) >>> in those non-qwerty M200s, and I think this research might help some other >>> people at some stage (this hobby is booming right ? :) ) >>> >>> We're (and I am) in the process of replacing the main rom + 8KB rom with >>> a 27C512 flashed with a custom "native Azerty" firmware >>> Which should free up to option socket, for a REX# >>> >>> I also plan to make other modifications to that custom ROM, but we'll >>> see if I get there. >>> I've also been experimenting in the past with custom firmware for the my >>> M102 for different reasons. >>> I'm a "modem" nerd and I have all the equipment (PABX, etc) to make >>> voice calls between my vintage laptops - so it's important for me to have >>> my modems work. This required a custom firmware to make my M102 work, with >>> modem, with a REX#. ( OK I think this kind of stuff is only relevant to me >>> this time :) :) >>> >>> >>> Le 2022-11-13 14:53, Brian White <[email protected]> a écrit : >>> >>> Nice. >>> >>> So the point would be to make the main rom natively azerty to match the >>> hardware, free up the option rom slot for normal use, without otherwise >>> changing the main rom so that it becomes incompatible with application >>> software? I guess you might even be able to make a dvorak version and move >>> the keycaps around? >>> >>> I'm just trying to imagine the sales pitch for that azerty 200 that >>> needs the option rom, thus preventing the use of any other option rom (or >>> at least making it pretty inconvenient by having to swap them on every >>> reset I guess?) >>> >>> "Here's your new model 200. It's only half as useful as others with no >>> modem and no option rom but you can still pay full price please." >>> >>> -- >>> bkw >>> >>> On Sun, Nov 13, 2022, 8:28 AM Stephen Adolph <[email protected]> >>> wrote: >>> >>>> hi folks, >>>> >>>> Thought I would share this work. It is a spreadsheet for computing the >>>> keyboard table in the T200 so you can make native custom keyboards for >>>> T200. >>>> >>>> Why? >>>> The AZERTY keyboard in Europe was accommodated using an option ROM that >>>> kinda hacked the keyboard. Keystrokes get intercepted and corrected to be >>>> AZERTY even though the main ROM is set up for QWERTY. >>>> >>>> An alternative is to have the main rom directly support AZERTY. >>>> To do this, there are 6 keyboard mapping tables that start at 9763h. >>>> Each table are 44 bytes long. >>>> >>>> This spreadsheet lets you assign the ascii codes for each of the 44 >>>> affected keys, for all 6 tables. (unshifted, shifted, GRAPH, shift GRAPH, >>>> CODE, Shift CODE). >>>> >>>> It is an excel spreadsheet that included the analysis add it so that >>>> certain needed functions are present. >>>> >>>> Once you make the correct keyboard mapping, the spreadsheet provides >>>> the 6x44 bytes in assembly compatible form, so you can compile and patch >>>> the tables with a hex editor. >>>> >>>> This approach could be used for other machines also. >>>> Note - the AZERTY keyboard did NOT modify the actual character set, so >>>> that is out of scope. Of course it is possible to patch the main ROM to >>>> change the bitmaps as well. Not handled by this spreadsheet. >>>> >>>> Comments welcome. >>>> Steve >>>> >>>> >>> >>> >>> __________ Ende Originalnachricht __________________________________ >>> >>> >>> *Vertraulichkeitsinformation: *Diese Nachricht ist vertraulich. Die >>> Informationen dieser Nachricht sind ausschließlich für die persönliche >>> und vertrauliche Verwendung durch den/die oben genannten Empfänger >>> bestimmt. Wenn Sie kein beabsichtigter >>> Empfänger sind, bitte lesen, kopieren und verwenden Sie die Nachricht >>> nicht. Machen Sie sie nicht anderen >>> zugänglich. Bitte informieren Sie uns umgehend über den Zustellfehler >>> und senden Sie die Originalnachricht >>> per E-Mail an uns zurück. >>> >>> >>> *Confidentiality Notice: *This message is confidential. The information >>> contained in this message is intended only for the personal >>> and confidential use of the recipient(s) named above. If you are not the >>> intended recipient, please do not >>> read, copy, or use it and do not disclose it to others. Please inform us >>> immediately of the delivery error >>> and return the original message to us via e-mail. >>> >>
