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MXV11 CA M8047 small system build CMD CQD and SCSI2SD

After a couple of busy weeks in work I've returned to this project. Thanks to TasKing for the SD RT-11 image. I can confirm this boots from the CMD CQD and SCSI2SD in my BA23 11/53 with no issue. If I put the SCSI card with SCSI2SD and SD card with RT-11 on in my 11/02 with MXV11 it doesn't boot although I can run the inbuilt SCSI utility on the CMD CQD. From advice I believe the 16K on the MXV11 isn't enough to boot the RT-11 image that I have. I have a spare M8044-DK MSV11 (status unknown) card so I thought that I'd add this card into the mix. I wanted to keep one slot to add networking but heh ho!. As this is the second memory card now, I've tried different switch configs from the manual and I can't get to the ODT prompt with this card in the system. I also have a DLV11-J (status unknown also) and I removed the MXV11, confirmed the DLV11-J is at base address and added this to the system with the MSV11 set at base address and I don't get the ODT prompt. I'm not sure if both cards are faulty or if I'm configuring something wrong or if I have an incompatibility. It would have been cool if this backplane was five or six dual slots and not four;)
 
I'm not making much progress with this. Is it possible to put an MSV11 card in with an MXV11? I can't figure out the dip switch setting on the MSV11. If I se it at base it will clash with the MXV11 but then the next setting is 32K and this leaves a 16k hole.
 
PG31 said:
I'm not making much progress with this. Is it possible to put an MSV11 card in with an MXV11? I can't figure out the dip switch setting on the MSV11. If I se it at base it will clash with the MXV11 but then the next setting is 32K and this leaves a 16k hole.
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An MXV11-AC (32 KB memory) should work with most of the smaller MSV11 modules such as the M7059,M8044 [ your card? ] or M8045) without a memory address gap. These MSV11's have starting addresses settable at 4KW boundaries. Note that the DEC manuals discuss the memory bank sizes as multiples of K which is typically Word, but many of the tables for address settings are in octal bytes (KB). It is easy to lose tract if you don't pay attention.

The MXV11-A only decodes the lower 16 bits of memory, so its memory can only be used in the low 0-32KW range.

If you have a large memory board, especially 128KW or larger, you may want to disable the memory on the MXV11-A. I've done this when with 11/23 or 11/73 processors so I can use the line clock and serial lines. See DEC µnotes 054 058 090 and 106 for more info on the MXV11-A.

Jerry
 
I've come back to this a after being busy with work. I would like to add them memory to 32K of memory on the MXV11 and not disable the MXV11 as it will still only give me 32K. I have an M8044 DK 32K 18 bit mos mem card. M8045 is also printed on the PCB. So looking in the manual this is MSV11-Ex I've tried the switches set to 1 and 4 closed for 320000 and also 1 and 5 closed for 340000.
 
PG31 said:
I've come back to this a after being busy with work. I would like to add them memory to 32K of memory on the MXV11 and not disable the MXV11 as it will still only give me 32K. I have an M8044 DK 32K 18 bit mos mem card. M8045 is also printed on the PCB. So looking in the manual this is MSV11-Ex I've tried the switches set to 1 and 4 closed for 320000 and also 1 and 5 closed for 340000.
Click to expand...


The M8045 PCB board was used for both the M8045 (18 bit LSI bus w/Parity) and M0844 (18Bit w/o Parity). See http://web.frainresearch.org:8080/projects/pdp-11/memory.php for some detail and images.

The starting addresses in the manual are Octal Byte Values. To start at the 32Kbyte boundary you need octal byte address 100000. Try switches 1,2,4 and 5.

Jerry
 
Thanks, Looking at the Frainresearch site I don't have parity on my board, I configured the switches as you recommended 1,2,4, and 5 on. Bingo! I now have 64K of memory and my 11/02 boots RT-11. Next I need to change the console SLU speed from 300 Baud. I need a shorter SCSI cable and then I can box it up. I'll post some photos over the coming weeks. I plan to at some point wire wrap the backplane to 22 bits so I can run an 11/73 with more memory.
 
I have now wire wrapped the baud rate to 9600 and RT-11 still boots ok but a lot quicker. Some photos attached of the finished machine booting RT-11 from SCSI2SD. 112.jpg111.jpg113.jpg114.jpg115.jpg116.jpg117.jpg118.jpg119.jpg
 
Thanks Jerry, your advice on the MSV11 switches got the ball rolling again when I was stuck. :D I have two more projects on the "burner", A MicroVAX 4000/60 and a HP 1000 A900. The A900 has issues and this is the project I will concentrate on next.
 
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