A 386 PC for Your RP2350
github.com140 points by SamuraiLion 6 hours ago
140 points by SamuraiLion 6 hours ago
Technically you could run OS/2 on it, I think.
Or Plan9 for i386.
Holy cow, a 386 with VGA and SoundBlaster on a $1 MCU?
I recall VICE emulating the Brotkasten on 386 PCs some thirty years ago, later UAE doing it for Amiga. How long til my currently running system (anno 2016) is being emulated?
It's really cool what can be done today with just an MCU that has sufficiently flexible IO. What's the performance like?
I had Slackware CDs in the nineties! They had a minimalist label and came with no jewel case (rubber band if I recall correctly).
I've been meaning to rediscover the CICA and Simtel collections. Maybe that's what I needed!
I love it! The RP2350 is probably the most underrated microcontroller available today.
Overrated surely? It's a pretty bog standard MCU, no wireless support, mediocre deep sleep. I don't know why you'd pick it over an ESP32 or nRF5x.
The only standout feature is PIO which is definitely interesting but very niche. It's also patented so say goodbye to any portability or FOSS vibes. (If you want a FOSS version btw, check out https://baochip.com/)
If it didn't have the Raspberry name behind it nobody would even have heard of it.
The PIO are pretty great and not niche. Almost any embedded application needs mixed signal interfaces. You could say embedded applications are niche, but not that embedded applications needing mixed signal interfaces.
A serious warning: read the RP2350 errata carefully. You may be better off buying old 2040 inventory.
RP2350 adds secure boot and encrypted boot. I am working on a little hardware device for a CTF and selected it as my MCU so participants can't just dump the flash to grab the flags.
Are you kidding me? It costs a fraction of the competition and you can use just about any pin for anything you want! It makes designing boards for the RP series so simple and easy!
Contrast that with STM32 where you have to constantly reference the data sheet to make sure you're using the correct pins for say, I2C when you're running in a particular mode. And since you're running in that mode, you now can't use other pins for certain things. Ugh! I hate it!
Then there's the issues with picking the right-size part number and making sure the pins you want are 5V tolerant, checking that you're using the correct ADC, and... Ugh! It's a pain in the ass!
Other chips aren't much better as they all have those same problems.
ESP32 is nice because of the zillions of built-in peripherals but configuring the damned thing can get really complicated really fast. It's so complicated, in fact, that they had to make a Makefile (as in `make menuconfig`) that rivals the Linux kernel in the sheer number of options/submenus.
Was the performance mentioned anywhere - I couldn't find it on the page?
Wow. How can it do this without an MMU?
MMU can be emulated as part of emulated architecture. Its totally possible to have software only mmu.
Does it emulate RS232 ports and printer ports as well ? I did'nt find anything. Then it would be possible to reuse old embedded equipment.
No, it doesn't.
Also this doesn't emulate ISA bus, where one could plug one of those "multi-io" cards to get rs232/printer ports.
Which is a shame. There are plenty of GPIO pins to fit full ISA on RP2350 (at least on "B" variant), and those GPIO are supposedly 5V-tolerant (with sufficiently recent silicon revision). So hardware-wise, it's just a matter of wiring up an ISA slot directly to the RP chip.
> Then it would be possible to reuse old embedded equipment.
Unlikely, virtualization/emulation has been a thing well before this project and you can just buy USB to RS232 adapters. There are GPIO solutions for industrial PCs other than the parallel port. Or you can simply buy new industrial PCs which have those ports.
If you find an industrial appliance controlled by genuine old PC hardware that hasn't been replaced, the RS232 ports are the least of your concerns.
In my experience, such machines usually have something insanely proprietary plugging into a custom ISA card, and whatever is connected to it usually doesn't take too kindly if the bus timings are off. And neither does the accompanying bare metal software that relies heavily on timing loops and hardware peculiarities.
Looks like it can even run Windows 96. Incredibly cool. I'll have to try if it runs my old Slackware kernal 1.2.13 some time. I used it with a 4MiB, 25Mhz 386 DX back in the time, so it should.
Did not realize that Win95 can technically run on a 20Mhz 386DX.
It "technically" can - i used Win95 on an AMD 386DX with 4MB of RAM back in the 90s for a little. Most of the time was spent waiting for the computer to do something while the HDD was constantly working.
The Pentium MMX with 32MB i replaced it with was MUCH faster, practically everything was instant.
Back in the mid 90’s I got it to “run” on a 386, but it was miserable. It was basically wondering if it was hung or just really slow on every command or mouse click.
Yes. I remember one of the MS guys saying the goal for win 95 was win32s equivalent performance on a 386 with 4 Mb ram. But win32s performance on that hardware was crap :)
> Win95 can technically run on a 20Mhz 386DX
s/technically/allegedly/
supposedly with a minimum of 4M RAM even! [1] I have a machine with twice that clock and twice that RAM that a friends parents wanted to toss out[2]. I spent the better part of a day getting Windows 3.11 and Office 4.3 to run. Playing around with it for a bit, I highly doubt that Windows 95 on minimum requirements would be anything but endlessly frustrating. I was not masochistic enough to try.
[1] https://en.wikipedia.org/wiki/Windows_95#System_requirements
We had Win95 running on a 25MHz 4MB FPRAM 286 back in high school. Poor teacher, half of first period was roughly how long it took to boot up, only for them to exit into DOS mode because the grading software and report card software was DOS-native and would hang if you tried running it under the GUI.
Good question. I ran Slackware Linux and DOS 5.0 on mine. I think Win95 was my Pentium 100 MHz already so it sounds a bit sus, but the FAQ section of OP had items about Win95, that is where I got the idea from.
(slackware) Just need to find where you stored all 20 floppy disks...
I think it came with two 3.5" disks, a bootdisk and a rootdisk, as well as two CDs. One was the actual distro, the other a sunsite mirror.
At least that is what I remember and while that memory might be hazy I know exactly where my precious is.
I definitely remember installing it off 20+ floppies onto a 386 back in the day. Most of the disks contained packages and you didn't need to install all of them though.
IIRC Emacs took up a significant number of disks
To be fair, that's pretty much an entire operating system. Just one that lacks its own kernel. It even takes a while to boot up!
Really cool, wondering if it can be ported to the PicoCalc.
Time to dig up 386bsd
yes, but those screenshots are EGA
nice job