would ts-dos fit on the main rom if SCHEDULE was taken off? Who uses that? ________________________________ From: M100 <m100-boun...@lists.bitchin100.com> on behalf of Kurt McCullum <ku...@fastmail.com> Sent: Tuesday, September 11, 2018 7:42:24 PM To: m100@lists.bitchin100.com Subject: Re: [M100] call for programs and games
This brings a question to mind. The Tandy 200 and NEC 8201 (and 8300) have multiple banks. Since the 27c512 is identical to the 27c256 ROM with the exception of pin 1 which is for address 15. Could a 27C512 be inserted with pin 1 bent to stick out to the side and then a wire run from pin 1 to the enable pin of bank 2? So switching banks also switches OptRoms? I have read an article about installing a switch to do this but I wasn't sure if this could be done by taping the existing hardware. Kurt On Tue, Sep 11, 2018, at 9:36 AM, Mike Stein wrote: Another simple approach that's often used is to have an adapter with an (E)EPROM large enough to hold several ROM images and a physical (or logical) switch to select among them (essentially what my adapter does, but with only one OptROM image). Unfortunately there's very little vertical clearance in these babies so there's not much room to use the old trick of stacking several chips with the select lines brought out the side. I haven't looked at my T102 but in the M100 there is enough room for one piggy-backed chip which would give you at least three 32KB OptROM images, but it does lift the keyboard slightly unless you remove the socket; depending on the socket used you might also gain some clearance if you trim the IC leads. Another approach to using several and/or larger ROMs is to make a little board that puts the chips upside down in the space beside the system ROM; as a matter of fact the plan with this prototype board was to add another RAM or ROM socket beside the existing one: [cid:9214B61DEE7143D89836A26EE9CD94D5@310e2] [cid:725B1C8D815D4C9DAAD31C91CC30ED7E@310e2] ----- Original Message ----- From: "Greg Swallow" <gswal...@mchsi.com<mailto:gswal...@mchsi.com>> To: <m...@bitchin100.com<mailto:m...@bitchin100.com>> Sent: Tuesday, September 11, 2018 9:34 AM Subject: Re: [M100] call for programs and games > Multiple ROMs would be easy enough with a REX. Of course if the REX goes, you > could be out of luck.
