Recent content by Steve Toner

I don't think it's a board position problem. The board layout couldn't be simpler: slot 1 has the KDJ11-D/S (M7554) and the RLV12 emulator is in the AB side of slot 2. Turns out the no output problem was user error (no surprise) - I didn't realize I had to reprogram the fuses every time, so...

Now we're getting nowhere! To rule out #2 above, I removed the CPU and memory from my 11/73, which has a SCSI controller, and replaced them with the KDJ11-D/S. It booted up fine, so no problems with the CPU module. And since it was out of the 11/53 case, giving me easy access to the RLV12...

Continuing the saga... Haven't reprogrammed the ATMEGA. But if I create a couple of RL02 partitions on the 2GB card and copy ZERORL.DSK to them, it does activate those partitions and shows them as DL0 and DL1. Copying a different disk image file, xxdp25.rl02, to one of the partitions causes...

Back at it... Tonight I tried (using same old firmware) a new 8GB SD card formatted as FAT32. It gives Error ID 82, same as the 32GB card. Formatting the 2GB card as FAT32, it acts the same as with FAT16. So it appears that what I've got running right now does not like SDHC cards (even...

Here's the latest: The posted source code and the hex file for the RLV12 emulator do not match. The source code won't build, as it tries to include a file named print-v1-2.asm, but the file that is there is print-v1-1.asm. If I change the include line, then it compiles but the resulting size...

I think I have to resolve the issue of the hex file not matching the source code first... And hopefully my stumbling efforts will save other people time and effort if they decide to try building one... It'll be pretty nifty when (if) it works, but there appear to be a bunch of pitfalls along...

I have found RL02 images to try. Whether they're working or not is still to be determined :) I'm pretty sure I tried a FAT32 partition as well without success, but I'm not near my notes at the moment...

Some minor progress... I started with a 32GB SD card but couldn't get that to work at all with the emulator. So dug out an old 2GB card and with that I am able to create blank partitions that it recognizes and loads. However, if I copy a disk image to one of these partitions it won't boot...

Making progress... Who had "mislabeled PC board" in the pool? I had connected the PC serial port to SLU0 originally. Looking at the Tx pin of (TTL level) USART0 (JP1) showed activity, but it didn't show up on the Tx pin of (RS-232 level) SLU0 (SV3). Because for some reason USART0 goes to...

Yes, he has instructions for formatting the SD card from a Mac (which I don't have). Each virtual disk is a separate partition of 20840 sectors of type "Linux". I used a Raspberry pi5 to set up (or attempted to set up) my SD card, but I don't think it's getting far enough to read it... I'm...

My first attempt at running with the RLV12 emulator have not gone well. I've got no output on the breakout board serial port - this could indicate a cabling problem or a problem with the ATMega1284P microcontroller. I used a TL866CS MiniPro to program the microcontroller, so I don't have 100%...

Looks like a clone of the HP Protocol Analyzer...

Hmmm... there are 6 +5V pins, so in theory 36A spread across those 6 pins (100% connector loading) is within spec (should be good to 6.64A per connector based on the connector chart, and assuming AWG18 wiring). But there's only about a 10% margin there, so I could see how a flaky connection...

OK, the connectors are rated at 11 amps: I derate this by 50%, and 2 wires should be sufficient to carry the 8A maximum that the power supply can provide, plus (on the ground side) whatever +12V current is required. Also, 18 gauge wire has 10 amp capacity at a 60 degree C temperature rating...

There's a fan. You can see the power leads to it in the interior view photo. The power supply can only supply a maximum of 8A@5V, so two wires should be plenty. I'll check the rating on the connectors, but I'm pretty sure they're up to the task. This is not going to be a big system - just...