On 11/22/19 2:36 PM, Al Kossow via cctalk wrote: No for RL. You, maybe thinking RX01/02 interchangeability.

Normally my answer would be "no". *However* there is mention that changing 3 jumpers on an RL02 will allow you to read an RL01 pack (not write). http://www.pdp-11.nl/peripherals/disk/rl-info.html So... Maybe. However right now I'm trying to get the disks up. It's been 20 years, and my cables are not in the best of shape. One cable seems totally dead, as the RL02 flunks when connected to the controller (DRIVE 0 and FAULT always on). With the second cable all lights are off and the drive spins up and goes ready, however as soon as I try to boot the drive goes to FAULT. If I remove the 0 drive selector and put in a 1, the fault goes out, however trying to boot DL1: gives the same error. This happens on both drives with two different boot packs (old RSXM38 images). So it is either the cable (possible as two pins were bent and needed to be straightened) or the controller (also a maybe, been 20 years I might have another spare somewhere around here). I'll order some DeOXit, ohm out the first cable to see if it's bad, and try again next weekend. Never dull. On the positive side I saved at least one set of RL02 rails. So there is that. C On 11/22/2019 2:36 PM, Al Kossow via cctalk wrote:

True. First cable faults hard (READY/FAULT on) no matter what. Second cable would turn off the Fault light and allow spinup (right direction) and ready. However when I tried to boot the drive went fault. Dug out a third (softer, less rigid) cable, same effect. Then I remembered I bought the controller working on Ebay some 25 years ago, so I went through my pile to find the original controller. Plugged that in... Drive booted to RSX11M+ 4.2. Great, I have a blown board and a good older controller. Enough to get going.... During all of this I had a minor setback: The MSV11-QC board (the one with 4mb of memory on it stock) failed startup diagnostics with what looks like a stuck bit. Used an 11/23+ to verify this and find the memory region, now I need engineering schematics for that board so I can replace one of the 41256 memory chips. On the positive side it looks like a pretty obvious stuck bit, just need to know which chip is at that address and memory location.... Fortunately I had a Clearmation (I think) backup memory board that has only 2Mb of memory. Enough to get going at least... Never dull. At least I can boot RL02's (will check more cables and such today) which means I can get RSX11M up and figure out what went wrong with my Hitachi ESDI disk (it's on an MTI controller which is *super fast). That's the gold standard, I think it's a 300mb disk in two partitions. One has RT11 on it (boots, limited drivers), the other has RSX11M 4.0 with all my code, games, programming languages, and so forth. When I try to boot that it faults to ODT, which could be a disk read failure or possibly something wrong with the monitor. RSX11M 4.0 was exceptionally finnicky when it came to devices and maybe something is missing and causing it to blow up.... C

Yeah, it's kind of cool but takes up an insane amount of space. For whatever reason I kept it through the decades and it holds the VT52 perfectly. Now I'm wondering if it's worth fixing the LS120 that's out in the shed. I sold an LA36 about a year or three ago, the LS120 was a weird duck: It's an LA36 body with the ability to go 300 and 1200 baud with 120 CPS printing. It does *not* have the logic of an LA120, the boards are more LA36 and it does not print bi-directionally. Just really moves the old head *fast* and probably has a bigger buffer to catch up during a carriage return. Maybe next year. On 11/22/2019 5:52 PM, Fritz Mueller via cctalk wrote: