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 Address	Ending Address	Length in words	Interrupt Vector	Device/Register
17765000	17765776	00000400		ROM 2
17772102	17772102	00000001		Memory CSR (2nd Module)
17772200	17772376	00000100		Separated I&D Registers
17772516	17772516	00000001		Memory Management Register 3 (MMR3)
17773000	17773776	00000400		ROM 1
17776500	17776506	00000004	300	SLU 0
17777520	17777520	00000001		Page Control Register (PCR)
17777524	17777524	00000001		Diagnostic Display Register (DDR)
17777546	17777546	00000001		Line Time Clock Register (LTC)
17777560	17777566	00000004	60	SLU 1
17777572	17777676	00000043		Memory Management Registers
17777744	17777752	00000004		Cache/Memory System Registers (17777750 = Maintenance Register)
17777766	17777766	00000001		CPU Error Register
17777772	17777772	00000001		Program Interrupt Request Register (PIRQ)
17777776	17777776	00000001		Processor Status Word (PSW)

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

Starting Address	Ending Address	Length in words	Interrupt Vector	Device/Register
17760500	17760516	00000010	320	DHV11 8-line Async MUX with DMA
17772150	17772154	00000002	154	RQDX1 RD51/52 and RX50 MFM Disk Controller
17772520	17777534	00000004	224	TQK25 TK25 Streaming Tape Drive Controller
17774400	17774416	00000010	160	RLV12 RL01/02 Disk Controller
17774440	17774456	00000010	s/w	DEQNA Ethernet adapter
17777170	17777174	00000002	264	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 .) 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 .

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