Basic Engine computer - 80's style

Peek

Hey everyone, I'm a newbie here but have spent the last couple weekends working on a basic engine computer. I figured I should introduce myself and share some pictures of it. The board itself I ordered from eBay. My plan was to find a chunky ps/2 keyboard to fit the basic engine inside. Ideally it should have enough space to fit the pcb, power switch, reset switch, playstation controller port, micro sd, a/v jacks, expansion header, and a power jack. After some looking around I found a Cherry MY-8000 on eBay. It is big and chunky plus it has a really cool magstrip reader built in. When you slide a card through it outputs the stored text as if you had typed it... Awesome.

Testing the basic engine with the keyboard.

I had to remove a lot of components in order to get it to fit... Thank god for that solder sucker! 😎

There were perfect round spots on each side so I could mount a 16mm diameter spst latching power switch with a red backlight, and...

A momentary spst switch with red backlight for the reset.

Here is the back cover showing the expansion header, micro sd & a/v jacks.

Here is the playstation controller port.

All finished! Finally I get to play with it 🙂

Guess I have to share 🙃

Peek

Oof. It looks like the images didn't post. The link to see all the pictures is here:
http://imgur.com/a/sT9HNPF

Peek

I'm going to retry my post original post with a different image attachment code... I can't delete or edit my OP so apologies in advance for spamming this thread haha

Testing the basic engine with the keyboard.

I had to remove a lot of components in order to get it to fit... Thank god for that solder sucker! 😎

There were perfect round spots on each side so I could mount a 16mm diameter spst latching power switch with a red backlight, and...

A momentary spst switch with red backlight for the reset.

Here is the back cover showing the expansion header, micro sd & a/v jacks.

Here is the playstation controller port.

All finished! Finally I get to play with it 🙂

Guess I have to share 🙃

Peek

For anyone trying to post images, don't use the 'add an image' icon, it does not seem to work. The good old bbcode for images works fine.

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jdoolin

Wow, what a great project idea. Really slick how you added the PS2 controller connector too. Nicely done on that. This gives me an idea.

I have a couple of Commodore 64 cases lying around whose motherboards are in disrepair. I also happen to have a C64 -> USB keyboard adapter. I was originally going to use it to house a Raspberry Pi. But now I'm considering using it for a Basic Engine (I bought enough components to build 5).

Or... hold on. Could I use it to house both? There's plenty of room in there without the motherboard. Perhaps I could add a switch to toggle between which board the keyboard is connected to.

My only problem (as seen in another thread) is that I can't get firmware to upload to the BasicEngine. But that did lead me to build another board, so I already have an extra to throw into the C64 case.

Shameless addendum: I uhh... also would be grateful for any help getting my firmware uploaded. I'm not sure how active this board is these days so I'm excited to see someone who got their BasicEngine working who may be able to give me a pointer or two.

Peek

Thank you!
I also considered using an old computer, but I don't have one on hand and I figured that I'd be better off using something that has all the standard keyboard keys. Also, I have a bad habit of allowing my projects to feature creep until it's out of my skill set, then it sets in a box on my very crowded 'unfinished projects' shelf. I think the challenge would be to get an old keyboard to speak ps/2 protocol... Short of extending the basic engine firmware, it might involve a separate microcontroller to interface it to the basic engine / raspberry pi. In the end I went with an existing ps/2 keyboard so that I might actually get this project up and running.

Sadly I can't give you much advice about flashing the esp8266 with the basic engine firmware. I purchased the basic engine PCB fully assembled and programmed. But I believe @bitartrate (here on the forums) is the same person who sells those boards on eBay so he may be able to give you some advice on flashing the firmware. I feel your pain though, I have very rarely had a project just go smoothly without any speedbumps. I'm sure you'll get it figured out though. Keep us posted!

jdoolin

Thanks! Hopefully he can help me out.

But back to that C64 idea. You can get an adapter called a KeyRah V2 that serves as an adaptor for a C64 keyboard to USB. I already bought one of those planning to use it for the RPi, and I haven't started that project yet (3D printing needs) so it could actually work for the BasicEngine, I think.

bitartrate

jdoolin Peek
I will be happy to help you with the flashing of the firmware. I will go to your post about it.
I looked at the KeyRah website and unfortunately they state that the KeyRah V2 adapter does not speak ps/2. The BASIC Engine uses older USB keyboards that "speak" ps/2 through the keyboard jack. I wonder what workarounds are available? It should be quite possible to use one keyboard adapter with both the BASIC Engine and R/Pi with a select switch or maybe key combination. I know that the arduino has been a solution for keyboard interfacing and adapting.

Peek

There ya go, then the only question is... does the KeyRah V2 have the ability to speak ps/2?
Do you have a 3D printer? Mine has been collecting dust recently, I have been doing a lot of projects by hand.

jdoolin

bitartrate Would I be able to use arduino as a USB to PS/2 (USB) adapter? That could be a fun project.

Peek

jdoolin I've used an Arduino 'Pro Micro' as a usb keyboard for a macro pad project. They can also easily read a PS/2 keyboard so I imagine the ability is there to read a keyboard directly via GPIO, and output via USB or PS/2 depending on which computer you're using. Maybe a GPIO to sense which one is turned on? I think the only hangup would making sure you have enough GPIO available to read all the lines on the keyboard (depends how it's wired)

bitartrate

jdoolin I do think that is very doable. I am not the best hardware person but I can see the steps to get there.
Using the next link as a guide:
https://www.petrockblock.com/2012/05/19/usb-keyboard-with-arduino-and-v-usb-library-an-example/
A. I think an arduino compatible with usb host capability is necessary and I think some of the Teensy microcontrollers have this onboard.
B. Using arduino library v-usb get the input from more-modern USB keyboard
C. Then send the input through the arduino PS2Keyboard library
D. Plug into keyboard input of BASIC Engine.

iabhua

I've picked up the same keyboard for about $12! Peek, you don't by any chance have a list of where you bought the SD extender and RCA cables? I really like the look of the SD card slot you made. Maybe even a complete BOM?

Peek

iabhua
Sure thing. Let me get a parts list together and snap some more pics of the inside. I may even have a little schematic. This is exciting! I absolutely love mine, and I am considering building another for my daughter who is very interested in learning to make little computer games. If you don't mind me asking, where did you pick up the keyboard for so cheap?

Peek

Apologies for the delay iabhua
Here are the parts I ordered (from amazon) in no particular order:

The RCA jacks that I mounted to the case:
https://www.amazon.com/gp/product/B07V1ZMP4B/ref=ppx_yo_dt_b_asin_title_o09_s00
(you can find these cheaper but I wanted ones marked red and yellow not black and white so I paid more for these)

The playstation controller plug was removed and reused from this controller extension cable:
https://www.amazon.com/gp/product/B07TYVGW1P/ref=ppx_yo_dt_b_asin_title_o09_s00

Here is the microSD extension cable (out of stock currently but there are many others like it):
https://www.amazon.com/gp/product/B07MYZXR6N/ref=ppx_yo_dt_b_asin_title_o09_s00

The power switch:
https://www.amazon.com/gp/product/B07FVHRM1F/ref=ppx_yo_dt_b_asin_title_o08_s00

The reset button:
https://www.amazon.com/gp/product/B07GTJBR59/ref=ppx_yo_dt_b_asin_title_o08_s00

I used the red backlit option for the buttons and also replaced the SMD green LED's on the keyboard (numlock, caps lock, scroll lock) with red SMD LED's. If I was keeping the green keyboard LED's I would have probably looked for a green colored backlight.

Here is the power jack I used. I had these on hand from a previous project and other sizes could be made to work. This one just fits in the opening left by removing the PS/2 cable from the keyboard.
https://www.amazon.com/gp/product/B077YHN1WQ/ref=ppx_yo_dt_b_asin_title_o08_s00

I have been swamped with work so I have not got a chance to crack it open for more pictures of the internals but I will make sure to do so this weekend.

Peek

iabhua

Here are some more pictures... starting with a little wiring diagram for the power & reset switch. I had to bend the terminals on the switch to allow them to fit (they are almost too long) & I clipped off unused terminals to save space. The switches may be damaged by holding the soldering iron on their terminals for too long, so be careful soldering to them. My wire routing here is sloppy looking in retrospect and the red duct tape holding the wires down is not my finest work lol. You can see in the pictures where I notched out for the micro sd extender. It's super glued to the back as are the PlayStation controller port and the header of the B.E. I used hot glue in strategic locations to further secure the B.E. board. I cut an a/v cable to use as an extension from the B.E. to the a/v jacks on the back of the case. If you have any questions, just ask.

Dmian

Wonderful project! Congrats!

Peek

Dmian Thanks man!