Does anyone know of any modern-ish laptops with a IEEE 1284 (aka parallel) port on them?
I’m running an IBM R52 laptop and the screen is dying; I’m going to attempt to replace the screen, but I thought I should try hedging my bets with a newer laptop incase things go badly during repair… also would not mind having a faster laptop.
The state of the screen currently:
Will this work for your use case?
Unfortunately not, the USB to Parallel adapters introduce too much random timing delay into the signal that can’t be accounted for. The parallel port is good for single digit microsecond timing determinism even running on Windows.
Some old Panasonic Toughbook ? There might be newer model with parallel port.
You’re right, I might have to resort to old toughbooks. I’m just semi-surprised the port doesn’t seem to be on laptops anymore when many modern mainstream motherboards still have the port.
I was also thinking that Express Card adapters exist… but then I realized modern laptops don’t have Express Card slots anymore either. It’s crazy how much we’ve regressed with laptop expandability.
I’m fairly sure that most “recent” chipsets do not implement LPT at all, that being said it’s quite a bit of a difference regarding implementations between controllers.
As far as PCI Express goes most common seems to be MOSCHIP/ASIX and Oxford. Oxford being regarded as the better but I wouldn’t count too much on it.
Also some interesting info here, FT232R bit bang timing | PushStack
If you really have to you can go m.2 pcie pcie lpt adapter then it’s all hardware with good timing.
You might also be able to use the tpm header on laptops that have it to expand the tpm port back into an isa port then use the isa port to get an isa lpt adapter
A thunderbolt enclosure with a pcie lpt adapter may still have good timings also
What are you exactly referring to?
Edit:
I guess the LPC stuff is ISA Over TPM To Your PC | Hackaday which is alpha stage at best and lack of DMA is probably a showstopper as it’s required for ECP mode.
It looks like the following motherboards should have native LPT off of their chipsets:
Asus:
Pro Q670M-C-CSM
Pro H610M-CT D4-CSM
Pro B760M-CT-CSM
Pro B650M-CT-CSM
Pro B560M-CT/CSM
Pro Q570M-C/CSM
Pro A520M-C II/CSM
Pro B660M-C D4-CSM
Pro B550M-C/CSM
Pro WS W680M-ACE SE
Pro WS W680-ACE IPMI
Asrock also has LPT on dozens of their LGA1700/AM4 motherboards (but seemingly no AM5) and MSI does to a lesser degree. I assume it’s built into the PCH on the boards because it would be alot of extra work to dedicate a separate chipset to it.
I know the issue of 5v tolerance shows up when using a separate chipset for LPT, some of the manufactures cheap out and only allow for 3.3v operation. You’re right that Oxford was one of the good manufactures that allow for “universal voltage” in their chipsets.
edit:
I just saw this possibly relevant LTT video about putting desktop motherboards into laptops
Yeah, Intel have a few desktop chipsets. Not sure if they support all modes but ASRock at least seem to list EPP/ECP modes in their manuals where Asus don’t so maybe only SPP?
Probably easier to by something like this then which comes with a port out of the box.
oh a bunch of the new N100 motherboards support LPT too, like Asrock N100DC-ITX and Asus PRIME N100I-D D4. and you’re right, it doesn’t seem very well documented in BIOS. looking around I only found the setting explicitly listed out for the Pro WS W680-ACE:
it even lets you pick the IRQ!! remember having to sort those out manually back in the day
ASRock refers to Device Mode in all their manuals (I’ve only checked 2 though) which appears to let you toggle between STD/SPP and ECP/EPP at least.
It also seems to be quite a pain to find a bracket with the correct pitch
