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DLV11J et.al. replacement

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cbscpe

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I seem not to be able to repair my Camintonn DLV11J board. I did replace the RS-432/232 receivers and transmitter and some errors have gone but others are still persistent. So I was thinking about a replacement custom board. I have various options and one option would be to implement a custom UART in a CPLD. I know that Michael has done a DC319 replacement in a ATF1508, but then you still need a lot of glue logic to interface it with the Q-Bus. So I had the idea of implementing a full DLV11 in a single CPLD and make the design in a way so I can have multiple CPLDs on a single board and at the same time add some features to make it look more like a multifunction board with line-time clock and bootrom and perhaps add a 5th UARTs to have a console and a full DLV11J. Typically a DLV11J has no programmable baud-rate but the DC319 has this option. Now I was asking myself how useful is it to have a programmable baud-rate? Any comments or suggestions and which OS supports this for a DLV11J?
 
The DLV11-E and DLV11-F had programable baud rates. I know RT-11 supports this feature in the later version.
 
It's hard to imagine how a programmable baud rate is useful for a one-of-a-kind interface. You're not going to be changing your baud rate on the fly. I assume the programmable case is to make Customer installation a bit easier for folks that don't do HW - but that's not your case.

Suggestion for the CPLD idea: Make a CPLD board that is like a "daughter board" to some other board that already has the Qbus interface functionality (such as your not-so-good DLV11J board). That is, take any suitable Qbus card, attach a bunch of wires to go to your CPLD, etc. You could consider attaching your daughter board physically on stand-offs, and allow the assembly to occupy two slots. If the daughter has PCB fingers, it can get power from the BP, and do bus grant for the second slot.

Pete
 
Now as you mention it I had to check again. Yes the DLV11-E and -F had programmable baudrates, but they use different bits in the XCSR as the DC319. In other words if I'm going to implement programmable baud rate then it should be in the DLV11-E/F style. However in the RT-11 command manual for RT-11 5.6 it says that you can only set the terminal speed for the DZ, DH and Professional 300 Series. As far as I remember the same is true for RSX-11M. So I really doubt that programable baud rate would be useful.
 
cbscpe said:
Now as you mention it I had to check again. Yes the DLV11-E and -F had programmable baudrates, but they use different bits in the XCSR as the DC319. In other words if I'm going to implement programmable baud rate then it should be in the DLV11-E/F style. However in the RT-11 command manual for RT-11 5.6 it says that you can only set the terminal speed for the DZ, DH and Professional 300 Series. As far as I remember the same is true for RSX-11M. So I really doubt that programable baud rate would be useful.
Click to expand...

In AA-M240E-TC_RT-11_System_Generation_Guide_Aug91.pdf it appears that if you do a sysgen and set XL$DVE the DLV 11E/F baud rate can be set with the SET SL SPEED command. To Pete's point, I'm not sure of the utility in a configuration were there is only one serial port, which of course would be the console. But i've patched RT11 for stranger things when trying to run the console from a third party terminal server or modem :cool:.
 
saipan59 said:
Suggestion for the CPLD idea: Make a CPLD board that is like a "daughter board" to some other board that already has the Qbus interface functionality (such as your not-so-good DLV11J board). That is, take any suitable Qbus card, attach a bunch of wires to go to your CPLD, etc. You could consider attaching your daughter board physically on stand-offs, and allow the assembly to occupy two slots. If the daughter has PCB fingers, it can get power from the BP, and do bus grant for the second slot.
Click to expand...

Most likely not, it is definitively easier to make a complete new design and add your own Q-Bus interface. Also I would like not to loose a slot in my small backplane.
 
I have decided to give it another effort and try to fix this Camintonn interface. I'm currently doing some reverse engineering and try to come up with a complete schematic (in Eagle) so far I have finished the CPU side (i.e. from the Q-Bus to the UARTs). And will now start the RS-xxx side (thew remaining 8 ICs dealing with the baud-rate clock generation, -12V generation and interface levels).

As for the self made DLV11J I have decided to take a completely different approach and instead of using UARTs I'm going to build a DLV11J compatible interface that has built-in USB interfaces, i.e. instead of having 4 IDC-10 headers it will have 4 (or 5) Micro-USB connectors where you can directly insert your PC or Laptop.
 
cbscpe said:
instead of having 4 IDC-10 headers it will have 4 (or 5) Micro-USB connectors where you can directly insert your PC
Click to expand...

Just wondering why multiple USB connectors? Since you can have multiple virtual COM ports on a single USB. Do you imagine needing multiple PC's connected at the same time?
Also note that via a single USB connection, there are "serial port boxes" that will break it out into several physical RS-232 ports. I used these boxes in our lab at HP (going the other direction) for doing testing on our storage boxes which each had two or more serial ports.

Pete
 
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