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.

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