Serial Connection for UVax II with H8571-B - test-drb@ccmp.vtda.org

24 Jul 2012

Tothwolf <tothwolf at concentric.net> wrote:

...
 On Mon, 23 Jul 2012, Kevin Reynolds wrote:

  Hey guys and gals,

 I have tried and failed to get a successful connection between my uvax 
 II and a pc rs-232 serial port.  The H8751-B didn't seem to work, so I 
 pulled it off and wired my own MMJ-DB9 connector.  I have tested the MMJ 
 cable, and it works flawlessly.

 For my connectors I have followed "The Cable" documentation at 
 http://www.mcmanis.com/chuck/computers/vaxen/panels.htm (chucks house of 
 vax), under "The MicroVAX II" section but it hasn't helped.  I have 
 tested the MMJ-DB9 connection from my uvax III consoles and from the 
 microvax 3100 and it works fine, so I think the PC side is working 
 correctly. 
The pinout for the cable at Chuck's House of VAX is correct. I just opened 
up the connector shells on my own cable which I assembled more than 10 
years ago and verified that it matches the information given there.

Your other option would be to use a H8571-B on the VAX side connected with 
an MMJ cable to a H8571-J (or equiv.) on the PC side. While the two 
adapters are both DE-9, the pinouts for each are very different.

I've used both solutions for my own systems, and I used to make and sell 
H8571-J "work alike" adapter cables on eBay (DE-9F adapter with crimpped 
pins to 6P6C jack, wired the same as a H8571-H, along with a 6P6C to MMJ 
modular cable; I sold 100s of those things).

If you'd rather not butcher an MMJ cable, I'd suggest finding an H8571-J 
adapter (useful with an MMJ cable for many other purposes as well). If 
someone else can't supply you with a second hand H8571-J, I do still have 
some NOS inventory (still in the original DEC bags) stored away (but not 
/too/ difficult to get to) but I paid a good bit for them so I can't just 
give those away. 