Does anyone out there knows about the SBC1190 from Micro/sys? I picked one up to tinker with. I've made a com port cable but what I really need is how to make a run/load cable so I can access the bios and flash the firmware. #oldtech #sbc #dos #pc104
#PC104
I don't suppose anyone out there knows anything about the Microsys SBC1190? It's an ancient #pc104 computer. Specifically I'm trying to find out how the special cable to switch between RUN and LOAD mode works. I'm guessing it just connects 2 pins on the serial header together but which pins?
Having failed to get my first version of the C011 #PC104 #transputer adapter to work, I've gone for a simpler approach.
This has just the Inmos C011, 5MHz oscillator, decoding logic (CPLD/74*245) and of course some LEDs.
I've added more this time which I hope will give me of an idea when something is working or not.
I've also brought in all 20 bits of the ISA address bus to the CPLD (not that I think I'll need it but just in case).
I've also used DIP chips in case I need change the speed.
Just to be clear:
The #tiny486 is intended as a #devkit for #i486 (in theory even #i386, #i8086 or any other platform that does #ISA (& #PCI) or where one's willing to accept less functionality of a #PC104 compared to #PC104Plus.
As a #BareMetal reference platform for #OS1337 / @OS1337 because there is a demand for a "#BridgeMachine" with new parts even if it's just to do #Archival and #DataRecovery duties and help setup modern drop-in replacements.
- I'd not be surprised if @TechTangents got contacted by some agencies that still have to deal with 8" FDDs and has to basically deny it.
I still think that a #tiny486 would be cool...
https://github.com/OS-1337/tiny486/blob/main/documentation/internal/tiny486-diagram.pdf
#PC104 #PC104Plus #RetroComputing #EmbeddedSystems #IndustrialComputing
NotLadp and NotSys are two addresses (0x150 and 0x160) and are asserted when the address matches.
PCLK is the ISA bus clock (14.3MHz on my #PC104 PC).
My logic here is that this is a 3 stage ripply counter.
When either address is invalid, the riple counter is reset (.ar = asynchronous reset).
So when an address is valid the IOCHRDY signal will be LOW, i.e. force a wait state.
Wohooo!!!
My #Transputer #pc104 adapter lives!!!
Turns out the CUPL code has two pins inverted (active low) that should not be inverted.
Same sequence of events on my pc104 PC controller by QBasic, I don’t get a response from the TRAM for first read :(
So something isn’t right with the PC timing or the CPLD.
#transputer #pc104
I’m getting nowhere with my #PC104 computer, basically it’s too fast for my needs (celeron at 1Ghz with 1Gb ram).
Does anyone have something sub 300Mhz in pc104 they would like to swap?
#PC104 #Transputer woes...
It seems I can write a value to the TRAM (a T425 based one) but when I try to read it back I get rubbish :(
This is my writing 0xAA55AA55 to address 0x8000FF00 (this is a valid address)
but when I read it back, I just get 0x10101010
Well the #PC104 #Tranputet link board is assembled. And it sort of works.
I can write to the link controller (0x150 base address) and I can send and read data through the link ports for the transputer. But (you knew it was coming right?) when I try and read the status from the control logic I get the wrong values, even though I can reset the TRAM and set the analyse signal.
So I’m a bit baffled.
Quick fit check of the big parts, everything fits.
I got lucky with one SMD part that if it had been slightly higher on the board it would have clashed with a part on the underside of the TRAM but I did have high 8pin headers just in case.
#Transputet #PC104
@timixretroplays yeah, I guess this shows @rasteri build this before businesses started upgrading tech.
I wished DM&P / ICOP would increase production or that there was an easier way to get other #ix86 SBCs from like #VIA (remember when they made #CUP|s?) or some #embedded variants from #Intel or #AMD.
Cuz I was shure some #IntelAtom SoC's and #AMDGseries APUs do have #ISA support as they use quite older process nodes and microarchitectures.
But for a #MSDOS #RetroGaming system, that is quite a bottleneck to work on when it comes to #BareMetal.
#DOSBOX or similar do work well, but they don't provide the necessary I/O for a lot of use-cases.
- I was looking at #PC104Plus (for my #tiny486 project) which just adds #PCI on the opposite side of the board to the ISA pins but otherwise retains #PC104 compatibility.
Maybe you can drop in a different #Vortex86 which also has #ISA?
- I know there are also Vortex86EX2 and others that may be an option...
The unelegant version would be to design a sorta "IDE Splitter" board to plonk in two of those single-port #IDE -> #SATA adaptors in and just set one to "Master" and the other to "Slave"...
Or just see if one can design a custom board instead with two SATA ports assigned to fixed M/S channels.
- Basically making it easy to plonk onto a #PC104 - style board and not have to deal with W I D E IDE cables...
@PaulaMaddox @polpo Personally I would but only on the SOM side as #PC104(-Plus) uses the fact that both #ISA and #PCI are first and foremost a passive bus each.
I guess @rasteri and other #PC104 users can now get the beloved #ISA-#USB #Flashdrive card with native PC104 pinout to stack on boards.
- Not that this is much of an engineering feat, as PC/104 is just a different form factor of ISA, but still nifty for #legacy / #industrial setups that may want to have more flexibility re: data storage.
I wounder if anyone got those ISA-USB controllers to work on #Linux distros tho.
- Obviously they're slow (according to @TechTangents in the realm of a 1x CD-ROM drive) and not bootable, but still useful for systems without native USB ports.
I sadly don't have any system with ISA or PC/104 at hand (gotta build one i.e. #tiny486) so I can't test it anyway, but maybe a future revision of the #WeeCee may benefit from such an option (which I think also has the potential to be a good "bridge machine" for people dealing with legacy / industrial systems...
Hooked up a display to my #PC104 computer and did a quick qbasic program and yup it works.
I need to do proper address decoding next.
That’s what the CPLD is for.
Given that I want to target i486 with @OS1337 but don't want to deal with obsolete hardware that is dying of old age, I think it's more fitting to consider a sort-of mainboard to shove some 486SX-SOM with PC/104-Plus on and have the few necessities hooked up to it. Maybe even put it inside a THINN #Pizzabox-style #case?
It would also make a new "bridge" machine to interface old PCI & ISA hardware and allow connecting i.e. a #QuadFlop and roll with that...
https://github.com/OS-1337/tiny486
Thoughts, @rasteri @polpo @TechTangents @lazygamereviews @foone ??
#Tiny486 #embedded #EmbeddedComputing #retro #RetroComputing #Linux #EmbeddedLinux #Development #DevKit #DevelopmentKit #ideas #concepts #Hardware #OpenSource #OpenSourceHardware #Mainboard #i486 #i386 #i487 #486SX #486DX #PCI #ISA #BridgeMachine #Bridge #PC104 #PC104Plus #OS1337
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