a bit provocative question about hardware design

[Oleg]

Hello everybody!

I'm new here but I have an important question about hardware design.

Why we have relatively expensive video board and and separate board for 3 buttons when you can have all of that with one inexpensive Raspberry Pico PI board (or onboard chip later)?

There is schematics and code with VGA and even DVI output from PI and for the price you can even add second PI just for USB and better debug interface.

For example https://picockpit.com/raspberry-pi/raspberry-pi-pico-video-output/

 

[x16tial]

The pico wasn't out when the X16 was in the design stage, which we are now way past.  I'm not on the design team, but I can tell you what they're going to say: no, the design ain't changing.  ?

Linked on the FAQ page are David's videos from 2 years ago about the design process if you'd like to learn more about it.

Now if someone wanted to incorporate a pico (or an RP2040) onto an expansion card to facilitate a USB interface (or anything else), I'd bet that's doable.  (I'm sure the same or similar idea has been mentioned elsewhere)

[rje]

2 hours ago, x16tial said:

Now if someone wanted to incorporate a pico (or an RP2040) onto an expansion card to facilitate a USB interface (or anything else), I'd bet that's doable.  (I'm sure the same or similar idea has been mentioned elsewhere)

Or anything.  Yeah, we've talked over options about what kinds of I/O to do with those expansion slots.  Arduino is preferred due to its voltage compatibility, but a Pi Zero is $5 and opto-couplers aren't that pricey, so....

 

[rje]

Perhaps something like the Pico is suitable for extending Ben Eater's 6502 projects.

 

[BruceMcF]

4 hours ago, Oleg said:

Hello everybody!



I'm new here but I have an important question about hardware design.



Why we have relatively expensive video board and and separate board for 3 buttons when you can have all of that with one inexpensive Raspberry Pico PI board (or onboard chip later)?



There is schematics and code with VGA and even DVI output from PI and for the price you can even add second PI just for USB and better debug interface.



For example https://picockpit.com/raspberry-pi/raspberry-pi-pico-video-output/

 

Partly because that is further away from what they wanted than an FPGA wired to be a row buffer VGA chip. If they could have found an introduction ASIC sprite and tile video chip that was appropriate for an 8bit CPU to drive, that would be the video solution. The closest they could find was the Gameduino FPGA design, but that had problems (including being implemented on a very old FPGA), so they put out a call for a new FPGA design.

Of course, there are heaps of projects that rely on modern high speed microcontrollers emulating old hardware to be driven by retro CPU's with 1/100th or less the bandwidth of the chip pretending to be its peripherals, there might not be all that much interest in YAPLADYSA (Yet Another Project Like A Dozen You've Seen Already).

Part of the point of having the Vera on the separate board in the CX16p platform reference design is so that if it's able to be built from a kit, the builder will only need to put on the connector for the Vera daughter board, and won't have to solder surface mount parts. The cost reduced CX16c would have the Vera circuit on he main board, and surface mount parts wherever it helps reduce TSC.

[TomXP411]

This is yet another VGA-over-GPIO design and is no different than:

• 
  Propellor
  


• 
  Geoff G terminal and Maximite
  


• 
  ESP32 VGA
  


• 
  Teensy VGA
  

Just about any microcontroller can output video to composite or VGA monitors with the right software drivers, but that doesn't make any of them suitable for integration with this system. The FAQ about the Propeller really applies to any microcontroller-based VGA solution. 

 

[BruceMcF]

 

19 hours ago, Oleg said:

Hello everybody!



I'm new here but I have an important question about hardware design. ...

 

7 hours ago, TomXP411 said:

This is yet another VGA-over-GPIO design and is no different than: ...

IOW, @Olegrather than being a provocative question, over the multiple years of the project it is a frequently asked one. But welcome to the project!