Pi pico Serial TTL

I need to use serial ttl ping on Raspberry pi pico.
I have an already tested ft232 and a ch340 with the appropiate level shifters.

But no signal comes out of any of the triplicated indicated pins.

Any idea?

As always, arduino mbed for pi pico, as confusing as always.

As guessed the pin indications are wrong, to send data to UART0 <-- yes 0!!
You must use Serial1 <-- yes 1!!

I already had issues guessing which of the 3 idicated SPI ports correrpond to real SPI port.

Please, somebody draw and publicity a pinout 4 the Arduino mbed os on rpi marking the right pins.

That's typical for many Arduino boards that has a native USB connection:
Serial: simulated Serial over USB.
Serial1: "first" hardware UART.

(Note that "first" is arbitrary, just like digital pin numbers. Serial1, Serial2, etc are high-level C++ objects that need not be associated directly with UART1, UART2, etc. (especially on the SAMD chips, where the USARTs are "Sercom" peripherals also used for I2C or SPI. The first two "Serial" connections on an Arduino 0 are Sercom0 and Sercom5.)

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No it all depends on the classification of the serial device as to whether the TX pin is an input or an output. Look up DTE and DCE.

Is it that hard to indicate which are used in Arduino mbed os (IIC,SPI,Serial)?

Or you just want every newbie to drop it's project because can't find the right pins, nor any documentation pointing which are the right ones?

Yes, if you are experienced and happend to have the appropiate equipment you will guess where to find the appropiate pins and c++ objects for each bus within minutes.

But the request is to have a simple and plain explanation is for newbies, not for an expert like you.

Nothing special about an LED and a resistor.

Way easier is not having to guess...

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Thank you.

I shall add: I bought 2 pi pico to use in an arduino project thinking i had 2 Serial-TTL, it turned out to be a lie.

Waster money, wasted time.

If only i had this picture, NOT THE DECEIVING ONE with 2 uart...

Now that i have discovered the official specification does not apply to Arduino mbed. Having only 1 serial, for a project that needs 2.

Shall i bury these things?, Smash with a hammer?

Like the SAMD boards, you should be able get another serial port with a little hacking. Are pins 8&9 OK?

If I understand the capabilities of the fancy "PIO" peripheral, you should be able to get an additional four UART ports using those. Possibly more, especially if some are uni-directional, or running at the same speed as other ports.

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Your error is taking the pinout published for the Raspberry Pi’s environment and trying to use it in the Arduino’s environment.

What you want to add a third type of equipment that has the serial ports miss labelled so that a TX port is always an output irrespective of what sort of equipment you have, just for you?

It looks like you can add Serial2 by putting

UART Serial2(8, 9, NC, NC);

At the top of your sketch. (output on pin 8, input on pin 9.)
(I tried it out and everything!)

(I don't think DTE/DCE has had anything to do with garfius's problems. And I'd be happy with boards always labeling the UART output as "TX" - DTE/DCE lost most most of its meaning back when PCs started connecting directly to mainframes, and the rest when actual "DCE" equipment (ie modems) essentially disappeared. It's completely ambiguous in the case of a microcontroller board, and quite arguably "up to a higher level of the implementation.)

PS: I got one of these neat little boards after a friend mentioned it on facebook. Rather handy - LEDs on every pin, plus assorted gee-gaws!

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WOW, it worked.

You really hit the nail!, come to my town i owe you a beer, cheers! :beers:

Btw, used: UART Serial2(8, 9, -1, -1);

I can only relay on things that do exist.

This is the reason i asked for the correct pinout for "Arduino mbed".

Just because i wasn't able to find it.

But luckily @westfw drew one, and even went further explaining a method to use a second UART.

Don't be so grumpy, help or don't answer,pls.

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