I/O Map and Other Hardware Stuff

I thought it was about time I decoded the I/O memory map I first saw at the initial power-up of the system. For simplicity's sake, I'd like to run the various hardware devices at their default addresses, and wanted to be sure nothing was going to conflict. Using the manuals for the KDJ11-A processor and the MVX11-B, I compiled the table below.

Starting AddressEnding Address Length in wordsInterrupt Vector Device/Register
1776500017765776 00000400 ROM 2
1777210217772102 00000001 Memory CSR (2nd Module)
1777220017772376 00000100 Separated I&D Registers
1777251617772516 00000001 Memory Management Register 3 (MMR3)
1777300017773776 00000400 ROM 1
1777650017776506 00000004300 SLU 0
1777752017777520 00000001 Page Control Register (PCR)
1777752417777524 00000001 Diagnostic Display Register (DDR)
1777754617777546 00000001 Line Time Clock Register (LTC)
1777756017777566 0000000460 SLU 1
1777757217777676 00000043 Memory Management Registers
1777774417777752 00000004 Cache/Memory System Registers (17777750 = Maintenance Register)
1777776617777766 00000001 CPU Error Register
1777777217777772 00000001 Program Interrupt Request Register (PIRQ)
1777777617777776 00000001 Processor Status Word (PSW)

I also looked up the defaults for the various devices I either already have or plan to use.

Starting AddressEnding Address Length in wordsInterrupt Vector Device/Register
1776050017760516 00000010320 DHV11 8-line Async MUX with DMA
1777215017772154 00000002154 RQDX1 RD51/52 and RX50 MFM Disk Controller
1777252017777534 00000004224 TQK25 TK25 Streaming Tape Drive Controller
1777440017774416 00000010160 RLV12 RL01/02 Disk Controller
1777444017774456 00000010s/w DEQNA Ethernet adapter
1777717017777174 00000002264 RXV21 RX02 Floppy Disk Controller

While I was at it, I looked out the cards themselves to see how they were set up. Most were already set to the default addresses, but it would seem that many were never actually used in the system, at least not as it's now configured. This was apparent due to the presence of jumpers on the quad-height cards which made them suitable for a Q/Q backplane, whist the H9276 is a Q/CD backplane. (The difference is in how the connectors are wired up - if you're that interested it's all explained here External link.) So, if I want to use any of these cards in the future, I'll need to break out the soldering iron and remove some 0Ω resistors...

I rounded the evening off by checking over the RL02 drives. I'd given them a quick once-over ofter cleaning them up, but not really done anything more than check the voltages. Although I'm still missing the RLV12 card to actually get them going (I have a couple of leads on finding one soon) all the cables are present, as is the terminator for the last drive. Everything is therefore connected up, ready for the controller's arrival.

One thing that was bothering me was that each drive showed a different combination of lights on the front panel when powered up. On one drive the FAULT and READY lights went on straight away, followed by the LOAD light a few seconds later. On the other, only the LOAD light was on. The first thought was that the first drive wasn't functional but, seeing as the drives weren't getting their clock signal from the controller, this light show is the expected result. The next question was therefore: why aren't FAULT and READY illuminated on the other drive? Turns out the bulbs were duds; replacing them with those from the other drive gave the desired result. For now I've borrowed the bulbs from both drives' WRITE PROTECT buttons to populate the more important indicators. All signs point to two working RL02s, but we'll only know for sure when they're hooked up and tested properly. Speaking of which, the XXDP tests for the RL02 can be quite impressive, as can be seen in this movie of the RL02 exerciser running External link.

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