Is there a BUG in the RX function of UART in Pico?

[TBWXY777]

Hello, I used the RX function of UART on the wokwi platform with both Uno and Pico. Uno works normally, but when I input to the serial port on Pico, there is no corresponding output and the browser becomes very stuck. Every time I input to the serial port, the stuckness will increase once.

The two projects tested on the wokwi platform are the following two. Pico:https://wokwi.com/projects/365662705015414785 Uno:https://wokwi.com/projects/365624339908814849

Maybe there is a problem with the way I use it? Could you please tell me the correct way to use it and provide an example of the RX function of UART in Pico if possible? Looking forward to your reply~~

[urish]

Hi, thanks for reporting!

There seems to be a bug in your Pi Pico code - it should call Serial1.read(), not Serial.read().

Nevertheless, it doesn't work even with Serial1.read(), seemingly keeping in the while loop forever.

Have you tried this code on the actual Pi Pico?

[urish]

Switching to Serial1 and compiling with the arduino community core fixes the issue:

https://wokwi.com/projects/365686547754485761

[TBWXY777]

Thank you for your reply, it is very helpful. I would like to know if I don’t use Pico on the platform, but use the code in RP2040js, similar to the following.

rp2040.loadBootrom(bootromB1);
rp2040.logger = new ConsoleLogger(LogLevel.Error);
loadHex(hex, rp2040.flash, 0x10000000);
rp2040.core.PC = 0x10000000;
rp2040.execute();

Then how should I switch between the official version and the community version?

[urish]

You just compile the code with the following Arduino core: https://github.com/earlephilhower/arduino-pico

I'm curious - what project are you working on?

[TBWXY777]

Wow, you reply so fast. I am trying to interact between multiple virtual devices because it seems that I can’t use multiple Picos or multiple Unos on wokwi at the same time. I have used the Arduino compilation library before to get the official and community version of the Hex code, but it seems that when the official version of Hex is injected into Pico, there will be some problems, such as the delay of delay() is not correct. Do I need to configure something else in the code?

[urish]

Trying :-)

Well, we're working on support for simulating multiple virtual devices (wokwi/wokwi-features#186).

As part of that effort, I'm planning to rewrite the clock implementation of this library, which will make it easier to implement accurate timing (e.g. for delay()). Right now, the timing is a bit flakey as the clock is tied to JavaScript timers.

[TBWXY777]

Okay, looking forward to your update~~