I've had a Mailstation for several years now, though I never really used it for what it was meant for. My ISP blocked outgoing SMTP, so it wasn't a whole lot of use to me. It was given to me initially anyway, so I wasn't out anything. But I wanted to know if the software could be replaced, so that perhaps I could get some kind of neat use out of it. Well unfortunately, not much was known at the time, and by the time I had started looking around here and such for ways to hack it, it seemed like development had hit a wall. So eventually I tucked the thing away under the bed, where it stayed for a long long time.
Then a couple months ago, I decided to check back here, and realized a few new things had been discovered about its internals and such. I also found out about the Yahoo Mailstation group, which I started perusing. I came to realize that in the time I had last looked into it, that someone HAD in fact figured out how to run code on the thing. Oddly, he didn't seem to really get any response to this at all, which made me think the Mailstation scene was completely dead. But I became interested enough to drag my Mailstation back out anyway, which had acquired a rather thick layer of dust!
And so, having poured over the hard work put into discovering how the hardware and firmware work, I've come fairly close to the point of being able to replace the software with something different altogether. Not with Linux though, to your disappointment I'm sure. Partially since it's much larger and more complicated than this simple hardware would handle well. And also because, to be honest, I don't know as much about Linux's internals as I'd like.
Instead, I started writing my own "operating system" from scratch, calling it FyOS. I decided to model it after CP/M where possible, perhaps to be able to port apps over to it at some point. But I've spent a lot of the time simply making a text console work, using the original CGA 8x8 font (all 256 characters) and turning the graphical LCD into the equivalent of a 40x16 character display. Routines to print characters to the screen work like a normal text display would, wrapping at the right column and going to the next line, and scrolling the screen when it hits the bottom. I even just recently added in key repeat and a blinking cursor.
I've released three versions, v0.01, v0.02, and just yesterday, v0.1. I didn't release source to the first, and the latter marked a branching in how some of the internals worked (bringing it much closer to OS-hood), so I didn't release source to it yet either (it's still messy). I did however release source and tools to make v0.02. The reason people might find this interesting is that it includes everything necessary to get code from a Windows PC to the Mailstation (via a parallel laplink cable). In particular, it includes files you can use with the SDCC C compiler, to write your own C apps using the text console interface. There won't be any key repeat or blinking cursor in that version (since the interrupt wasn't hooked), but some people might find it fun to mess with nonetheless. Writing text to the Mailstation screen in C is truly as simple as a printf statement. And reading input is just as easy.
This might all seem like a shameless plug, but I'm really excited for the development of this thing, and have stuck to working on it for the last two or three months now. I would have never guessed I'd have been able to come this far in developing for it, and so I hope it'll be of some use to other people as I go! The Yahoo group is just so quiet most of the time that I figured posting here might attract some other interest, for people that didn't realize what had been going on since anything was posted here last.
Yahoo Mailstation group, where I made a bazillion posts and asked lots of things, resulting in lots of useful info:
In particular, the thread where I introduced FyOS, where you can get more details on it and the other two versions (since I replied to myself for those):
A placeholder page on a server of mine, which has links to the file downloads, and some pictures of work I've done along the way, until I get around to making a better site devoted to it all: