PDP-11/05 Console Adapter V2

[Dare]

For those enthusiasts of the PDP-11/05 and 11/10, over the past year or so I have been working on a new version of my PDP-11/05 Console Adapter project. The project implements USB and RS-232 interfaces to the PDP-11/05’s console (SCL) port. (For anyone unfamiliar, the PDP-11/05 uses a TTL-level console interface with some odd signaling, requiring conversion circuitry to interface to a standard RS-232 terminal).

The previous version of my project was based on the Teensy 3.2 microcontroller board, which which has since been discontinued. The new design is built around the (amazing) Raspberry Pi Pico, which is readily available and cheap.

Version 2 of the Console Adapter is a complete redesign of the original concept, with a new schematic and entirely new firmware. There is also a PCB design that is ultimately intended to fit within a 3D-printed case (hopefully coming soon).

The new firmware provides the same basic functionality as the original, plus a number of new features:

• A virtual paper tape reader that uses the 11/05's READER RUN signal
• An M9301/M9312 console loader that can load data directly into memory using console commands
• A flash-based file library for storing frequently used paper tape images
• XMODEM support for uploading tape images to the PDP

The project is entirely open source, and all code and design files can be found on my github site: https://github.com/jaylogue/pdp1105-console-adapter-v2. There is also a User Manual.

Finally, I’m able to provide a limited number of assembled and tested units for anyone who has an 11/05. DM me for details.

 

[czunit]

I'm trying to remember: If I have a DLV11 on my 11/05 serving as the console, does that auto-disable the internal one?

 

[Dare]

I'm trying to remember: If I have a DLV11 on my 11/05 serving as the console, does that auto-disable the internal one?

No. In fact, I'm pretty sure there is no way to disable or change the address of the internal uart on the M7260.

 

[thunter0512]

According to gunkies.org, jumper W1 on the later revisions of the M7261 when installed disables the built in serial interface. I have not tried this myself. I suspect that earlier boards could also be modified to add this feature.

 

[Dare]

According to gunkies.org, jumper W1 on the later revisions of the M7261 when installed disables the built in serial interface. I have not tried this myself. I suspect that earlier boards could also be modified to add this feature.

Ah. I think I knew that at one point, but forgot.

That jumper definitely doesn't appear on my early rev board. And it looks like the circuits are different enough that it might be hard to achieve on the older board.

 

[thunter0512]

For those enthusiasts of the PDP-11/05 and 11/10, over the past year or so I have been working on a new version of my PDP-11/05 Console Adapter project. The project implements USB and RS-232 interfaces to the PDP-11/05’s console (SCL) port. (For anyone unfamiliar, the PDP-11/05 uses a TTL-level console interface with some odd signaling, requiring conversion circuitry to interface to a standard RS-232 terminal).

The previous version of my project was based on the Teensy 3.2 microcontroller board, which which has since been discontinued. The new design is built around the (amazing) Raspberry Pi Pico, which is readily available and cheap.

Version 2 of the Console Adapter is a complete redesign of the original concept, with a new schematic and entirely new firmware. There is also a PCB design that is ultimately intended to fit within a 3D-printed case (hopefully coming soon).

The new firmware provides the same basic functionality as the original, plus a number of new features:

• A virtual paper tape reader that uses the 11/05's READER RUN signal
• An M9301/M9312 console loader that can load data directly into memory using console commands
• A flash-based file library for storing frequently used paper tape images
• XMODEM support for uploading tape images to the PDP

The project is entirely open source, and all code and design files can be found on my github site: https://github.com/jaylogue/pdp1105-console-adapter-v2. There is also a User Manual.

Finally, I’m able to provide a limited number of assembled and tested units for anyone who has an 11/05. DM me for details.

View attachment 1302784

@Dare I read through the detailed description on GitHub. I love the rich set of features and the flexibility. Very nicely done!
You wrote about a "snag" with the enclosure design. What is nature of the snag? The adapter would be more practical with an enclosure.
Thanks for making this available.

 

[czunit]

According to gunkies.org, jumper W1 on the later revisions of the M7261 when installed disables the built in serial interface. I have not tried this myself. I suspect that earlier boards could also be modified to add this feature.

That sounds right. When I ran it 30 years ago it had no issues with the DL11, so I must have set that jumper.

C

 

[Dare]

@Dare I read through the detailed description on GitHub. I love the rich set of features and the flexibility. Very nicely done!
You wrote about a "snag" with the enclosure design. What is nature of the snag? The adapter would be more practical with an enclosure.
Thanks for making this available.

Thank you.

I don't have any 3d printing skills myself. But I was connected with someone who's built a number of cases for hobby projects before and volunteered to help out. Unfortunately he's gone silent as of late (I get it... life!). So I'm still working out how to proceed.

The concept for the case is pretty cool. The intent is to have two variants: one freestanding case which has the ribbon cable connector out the side (like in the picture), and a second case which has a female IDC connector protruding from the bottom. The second case would plug directly into the back 11/05 (i.e. without a cable) and would anchor to an existing screw nearby the SCL connector. The PCB was designed to work in both cases. Unfortunately, because the case dimensions haven't been finalized yet, its possible the current boards I'm assembling won't fit in the cases without some rework.