Pi4 and v1 kits

Building Zynthian
12

Hi, so is It only my problem? Nobody find that kind of behaviour while upgrading v1 with prototype 4 wiring to raspi4?

13

I am sorry I am annoying but if someone can check if kit v1 and prototype 4 wiring works with rbpi4 I will be extremely grateful. I’m not able to make encoders work.

14

I will try with an old v1 that i’ve somewhere …

15

I’ve just swapped out my v1/prototype-4 from rbpi3 to rbpi4 (recent Buster image) and I am also seeing encoder issues.

The Back and Select buttons don’t work, and the Layer and LoadSave buttons do work. The encoders don’t do anything when turned.

16

That’s exactly the issue. Thanx. Unfortunately I do not know nothing about solving this problem. Our Only hope in @jofemodo :smirk:

17

Its probably more accurate to say the Select encoder doesn’t work, and without a working Select button it is not possible to navigate to a screen to try the other encoders

18

Have you tried a USB keyboard? There are keymappings that will allow you to navigate around a bit, and you might be able to figure out if the other encoders are working.

19

Is there any knowledge that new rbpi4 has any differences in gpio pins layout comparing to rbpi3? Is this possible that is source of v1 kits problem?

20

What I have tried is the touchscreen, which works. So I can navigate to a screen which confirms all the GPIO based inputs don’t work. The 2 buttons which come through the MPC23008 work fine.

I’ll have a play now with python gpiozero to see if I can read any GPIO input events

21

The following script

#!/usr/bin/env python3

from gpiozero import Button
from signal import pause

b13 = Button(13)
b13.when_pressed = lambda: print('13 on')
b13.when_released = lambda: print('13 off')
pause()

produces output when the back button is pushed:

root@zynthian-2:~# ./button.py 
13 on
13 off
13 on
13 off

So it seems zyncoder needs a fix for GPIO setup or input reading

22

OK, it looks like the author of wiringPi has hit a wall and declared wiringPi EOL while acknowledging that there are issues working with the Pi v4.

When I run watch gpio readall I don’t see changes when buttons are pushed, so this is definitely an issue within wiringPi. (and this was even with his binary-only 2.52 package which has no corresponding source release :grimacing:)

I’ll look for forks on github to see if anyone is maintaining a fork which works with v4. Maybe longer term this is a chance to move away from wiringPi’s pin numbering - its pretty confusing :wink:

23

It’s quite strange your case. I’ve do some research, but i can’t find any reference about pin differences at boot up. Of course, the RBPi4 GPIO is much more configurable and almost every pin have several modes (GPIO, I2C, SPI, UART, etc.) Perhaps some problem with the wiringpi library … i don’t know …

24

It really does look like wiringPi is broken on 4B, is unmaintained, and has no regular source code releases.

25

gpiozero supports wiringPi pin numbers by doing new Button(‘WPI23’), and there is an unmerged pull request to add support for the MCP23008 and MCP23017

I realize it would be a bit of work though.

26

I see. I just read your link. I will start looking for alternatives … but we need a C library for zyncoder. I would check:

Anyway, it’s a big change and i would prefer that wiringpi could be saved …

Regards,

27

So, maybe it is time to upgrade our v1 zyntians to v2 or v3. Maybe It would be safer for the project overall. @jofemodo, what should i order to update my old construction?

28

Would it be better to switch over to i2c encoders? I love the simplicity of these, plus the added RGB. I don’t need a MIDI DIN, they would eliminate the need for a custom MCP23017 board like I have now in my DIY Zynth.

1 Like
29

Yeah, I’m just trying to save money and time, and I would prefer to have an all-in-one board.

If it is declared that prototype setups and Pi4B are incompatible then I’d upgrade and move on.

The fact that wiringPi is unmaintained and its GPIO support is broken on the 4B means there is a risk that i2c support might break for some future raspberry pi hardware release

30

These look nice, and I wouldn’t miss legacy MIDI.

31

Isn’t it possible somebody will step up and maintain WiringPi?