SCHEDL and ADDRSS could both go for me, but I suspect they are pretty small
On Tue, Sep 11, 2018 at 3:56 PM, you got me <ven...@hotmail.com> wrote: > 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: > > > > > > ----- Original Message ----- > From: "Greg Swallow" <gswal...@mchsi.com> > To: <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. > > >
