Linux on a cash register

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The video chip on the motherboard is a 1MB Cirrus Logic. No thanks. I had an old Voodoo3 card in my junk drawer and I threw that in there. It powered up and everything. You can't see it well in the picture but it's there. Hot, too. I probably won't be able to keep it in there with the case on. But I want to be able to play Doom eventually. So I'm going to have to find a free 4MB whitebox S3 card or something. That means a trip to the attic later.

I replaced the drive it came with with an old 4GB IBM I had laying around (remember that I wanted to save the stock drive so that I could look at it), ran some CAT5 from my switch to that little RJ45 jack, and started to boot Linux. We've got trouble, though. Red Hat won't install.

Problem one is that there isn't enough RAM. Even an older Red Hat like 6.2 won't like 4MB of RAM. And while I do have a copy of Red Hat 4.2 (and I have a Linux-on-a-floppy deal from the Linux Router Project which I used to use a a gateway/firewall) which might work, 4MB is just nasty. I did try installing with "linux mem=4M" at the expert prompt, but it didn't take. It hung right at the part where it tries to read from the initial RAM disk. I tried passing it "mem=2M" to see if it got conservative. It was conservative all right. It used the hard disk (I could hear the disk running) but when it tried to decompress something (couldn't tell what) it kernel panics with a really cool error message saying that lower memory address such-and-such was being overwritten by higher address so-and-so. It needs more RAM.

Problem two is that RJ45 jack on the motherboard. I don't know what it's hooked up to, but it's not an ethernet transceiver. I suspect it's another serial port, like for opening the cash drawer when there's no printer hooked up or something (the printer has a little RJ45 jack that connects to the cash drawer -- which I don't have yet -- and some signal or other opens the drawer). I found an old Netgear FA310TX (which is probably the best ethernet NIC ever made) and threw it in there under the Voodoo. Looks like I have link. I should have checked for link before, but I'm an idiot. Added to my project list is to snoop that RJ45 serial port and find out what it is. Setserial will be my friend.