75D First Steps.

[rprosperi]

(04-21-2021 11:10 PM)Paul Berger (Canada) Wrote:  

(04-21-2021 09:06 PM)rprosperi Wrote:  Congratulations on a good deal! You can't win if you don't play...

By hidden optional ROMs, are you suggesting some ROMs may be installed inside? Though likely possible from a h/w perspective, and despite being fairly common for 41C and 71B machines back in the day, I don't recall this being done with the 75C/75D. No doubt that was partly due to the very high cost for these machines, but I'm also not sure if 4+ ROMs could be installed (logically) at the same time.

@anyone - is this feasible and do you recall this being done?

I don't think it would be feasible there is very little empty space inside a 75, but there would be room inside a pod, especially if you chucked the 300 baud modem, in fact I have toyed with the idea of a PMS like device inside a pod. I have built a read only ROM emulator but it still needs work, I will have to get back to that one of these days. My ultimate goal would be an expanded PMS like device that uses nonvolatile memory like FRAM.

Paul.

Thanks Paul. I have a Pod ready to lose its modem when you're ready...