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Comment by drivers99 | Hacker News Reader

Can’t wait to check this out on my IBM PC (5150) with CGA which is my first computer that I still have. (Some of the RAM is bad though so if it needs the full 640k like 8088MHz did I might need to repair it.)

Then again 8088MHz worked well for me because I lost the RGBI monitor for it at some point and that demo is designed for composite.

Getting files to the PC is an interesting challenge. Have to copy from Windows 10 or 7 to a USB drive and movie that to a PC I have with a serial port and Windows XP and then transfer the demo with Hyperterm in Windows and Telix in MS-DOS on the PC side via null modem.

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If you can put USD 50-100 in your antics, you may add an XT-IDE ISA card with a Compact Flash adapter.

The one I have has a slot in the backside metal bracket: I can load a Compact Flash (1 GiB, FAT-32 formatted) in a modern PC with a USB adapter, then I insert the Compact Flash in the back of my IBM PC and switch it on with new fresh data and software.

Note that the Compact Flash is seen by DOS (6.2 in my case) as a hard disk drive, you may boot on it. It may also co-exist with an MFM harddrive: in my case, the MFM drive is C: and boots, the Compact Flash is D:.

It is a very convenient setup to make the IBM PC a smooth place in our modern IT world.

> Getting files to the PC is an interesting challenge.

I just put a NIC in mine and use the mTCP utilities. Easy as pie :-))

https://www.brutman.com/mTCP/

Interesting that this isn't based on lwIP. lwIP can operate happily in just 1 kilobyte of RAM, although lower RAM limits hurt performance quite heavily (can't reorder TCP packets, so you have to wait for the far end to retransmit them if they arrive out of order).

Mike wanted to write a TCP/IP stack.

Adding to the other comments, there are also SD card/flash drive-based 'floppy disk' hardware emulators available on eBay. They even have buttons on the front so you can cycle through, e.g. all thirteen floppies of Windows 3.1. :)

There's one piece of hardware (3.5" hardware emulator) whose clones are popular enough to even have third-party customizable firmware on github!

I own one, but unfortunately, I can't remember the name of this hardware nor the alternate firmware off the top of my head. When I get to a computer I will check my ebay history.

Even though it's physically a 3.5" 'drive,' with the IDC-style connector, the alternate firmware lets you emulate various disk geometries, and I believe the 3.5" and 5.25" signals are electrically compatible.

It's an extremely useful piece of hardware, especially if you're already getting software in the form of floppy disk images from a place like winworldpc.

Gotek?

That's the one. Thank you.

FlashFloppy. The hardware is a commodity. Software (firmware) is what matters.

https://github.com/keirf/FlashFloppy

USB-to-serial adapters are widely available, AIUI.

I bought a random one online recently in order to configure an embedded device that requires a serial port, and it worked perfectly out of the box immediately. I used it with minicom and felt nostalgic!

I don't know about the 5150 in particular, but most of these USB to serial adapters will not work with older computers since they are expecting different voltage levels.

I wouldn't know if 'most of them' don't work, but I know for a fact that I have one (made by Vivanco, using a Prolific chip) that works fine in combination with my IBM 5160. I use it in combination with FastLynx, which still works even under Windows 11. It's the only one I've tried, so I've not encountered any that didn't work.

All of the genuine name-brand ones work fine, stick to older Prolific (the ones Tripp-Lite included with UPSes are great!) or genuine FTDIs.

cp2102 is my standard recommendation, as they are cheap, do what they're meant to do and cause no trouble.

FTDI were good, but they went apeshit with the drivers bricking non-genuine devices, and I don't wish to support them if at all possible.

Prolific have always been troublesome, and their proprietary drivers refuse clones these days (which broke my chinese usb-rs232 dongle).

ch340 is very popular these days, but I've found they have little tolerance for slightly-off or jittery clocks.

Current limits usually make this Just Work: clamping diodes sink enough current to drop the voltage from 12V to 5V (or whatever) and the thresholds in the reverse direction are defined so that a 12V circuit still sees 5V as high if there isn't a terrible amount of noise.

Of course, this all depends on sane current limiting behavior from the 12V side. I'm sure there's at least one line driver out there that does a good "gnome swapping terminals on a car battery really fast" impression.

Just to clarify: it is not simply a matter of RS-232 (potentially) going up to 12 V. The low signal level is between -3 V and -12 V. If the adapter complies with RS-232 specifications in this respect, it should work with older hardware. If it doesn't, then there is a good chance it won't.

Unfortunately, many adapters advertise being RS-232 but the specifications go on to say they are TTL. (I'm not sure that's accurate either, but it is the vendor's shorthand for 0 V and 5 V levels.) Some won't say anything at all, which leaves compliance an open question.

How big are they? I still have a 3.5" floppy drive in my daily driver PC if that helps.

The demo is about 500kB at the moment. We're hoping to fit the final version onto a single 360kB floppy but didn't quite get that working in time for the party. A 3.5" floppy should work fine.

That made me curious. How is the floppy drive attached to the PC?

I haven't seen a FDD controller in a new motherboard in a very long time. I use GreaseWeazle[0] for my floppy needs.

0. https://github.com/keirf/greaseweazle/wiki

It's a USB floppy drive, slim model YD-8U10-2, that replaced the stock drive in a 5.25" Rosewill RCR-FD400 media reader unit.

https://www.newegg.com/rosewill-rcr-fd400-74-in-1/p/N82E1682...

https://web.archive.org/web/20100130173743/http://www.geeks....

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