New Raspberry Pi Controller

[TGB1718]

Just in case you haven't seen this, I know lots of us use Micro-Controllers to interface our beloved 8 bits to the

outside world, this has just been released "Raspberry Pi Pico"

https://thepihut.com/collections/raspberry-pi-pico?mc_cid=175b11e789&mc_eid=07165e7cc4

 

133Mhz ARM CPU lots of GPIO pins and of course very small, a nice cheap addition to make more fun

 

[gozar]

On 1/21/2021 at 5:35 AM, TGB1718 said:

Just in case you haven't seen this, I know lots of us use Micro-Controllers to interface our beloved 8 bits to the

outside world, this has just been released "Raspberry Pi Pico"

https://thepihut.com/collections/raspberry-pi-pico?mc_cid=175b11e789&mc_eid=07165e7cc4

 

133Mhz ARM CPU lots of GPIO pins and of course very small, a nice cheap addition to make more fun

 

I'm assuming it's 3.3v and not 5?

 

[+fdr4prez]

36 minutes ago, gozar said:

I'm assuming it's 3.3v and not 5?

 

that is correct

[+fdr4prez]

they are at Microcenter, but they won't ship it, so pick up only.

 

They are out of stock at Adafruit

[+fdr4prez]

Compare the Arduino Uno to the RPi Pico

 

Raspberry Pi Pico Board Comparison | Pico or Arduino UNO? (sb-components.co.uk)

[gozar]

On 1/22/2021 at 2:22 PM, fdr4prez said:

that is correct

A review I saw said they are 1.8v to 5.5v.

[NISMOPC]

"...the Pico uses a 3.3V GPIO. This could be seen as a con, but many components can be used with 3V and 5V voltages, and those designed for 5V can still be used with 3V via a voltage divider or a logic level converter board."

[NISMOPC]

I tried Rasp Pi OS and the Atari800 emu on a Pi Zero W. It works, but there are nuances. Choppy sound and slight delay in activity as well as slow controller response. Probably milliseconds, but definitely noticeable.

 

Ended up swapping the MicroSD into a Pi 3B and it runs flawlessly.

 

Would be interesting to see how the PICO controller can handle an Atari 8-bit emulation based on the videos from the other link. 

[TGB1718]

2 hours ago, NISMOPC said:

I tried Rasp Pi OS and the Atari800 emu on a Pi Zero W

Had the same problem with a Zero W , a quick look and it showed it was at 100% CPU all the time, like

you I moved it to a Pi 3B and all was fine, 

[gozar]

On 2/18/2021 at 11:58 AM, TGB1718 said:

Had the same problem with a Zero W , a quick look and it showed it was at 100% CPU all the time, like

you I moved it to a Pi 3B and all was fine, 

 

That's weird, I'm running atari800 on a Pi A without issue. But, I'm not launching X, so maybe that's the difference.

[NISMOPC]

43 minutes ago, gozar said:

 

That's weird, I'm running atari800 on a Pi A without issue. But, I'm not launching X, so maybe that's the difference.

Well...   I was on a mission. A painful, yet satisfying mission.

 

I successfully got one of my Pi Zero W's to run Atari800 smoothly.

I installed DietPi with no desktop and no additional features except OpenSSH so my PC can talk to it when needed. Set the GPU memory at 256 and CPU is defaulted to "On Demand". So pretty much stock except for GPU setting.

 

Atari800 runs flawlessly so far. Been testing it last night and today and have not found any issues so far. Mostly *.xex files. Need to do more testing with other, especially *.atr files. Been very pleased with the performance.

 

Only oddity: For the first min or so, games/sound are choppy. After that - smooth as could ever be for a emulator. I even compared run times of games and sounds with videos of actual hardware of same games and could not tell the difference.

[TGB1718]

13 hours ago, gozar said:

That's weird, I'm running atari800 on a Pi A without issue. But, I'm not launching X, so maybe that's the difference

Pi A will be fine, it's the Zero W that has the slowdown, but as @NISMOPC has done, if  you strip out all the stuff you don't need it can be ok.

[Dr Pinball]

Just started working on a cartridge emulator for 2600 using the Pico, code here:

https://github.com/sigmafx/atari_pico

Uses PIO to sample the address lines, interrupt to get the ROM data and PIO again to set the data bus.

 

For a 2K rom Pico was happy to run at stock 125MHz, but for a 4K rom I needed to overclock to 250MHz, not sure why, maybe memory access is too slow across the larger rom size??

 

I'm not going to finish this to a complete cart emulator, I just want to be able to quickly transfer roms to see the results of development work, so send rom over serial link and start execution. I'll put together a cart pcb with address line buffering for 5v to 3.3v - data lines work fine at 3.3v.