asyncio_serial for ESP32

[garykuipers]

Two questions:

1)Searches in google about asyncio serial tends to give examples with "import_asyncio_serial", but it is not installable via upip.install. Can someone point me at where I can find this module?

2. Mode generally: Is there a tutorial that explains how to access resources in case one tries to upip.install them and they are not available? I know about searching this Github area. Often the things that are mentioned in examples are not found in this micropython area.

[sosi-deadeye]

#10474

[peterhinch]

Also here.

[garykuipers]

Thank you Peter: I am halfway there: The transmit works, the receive does not work for me. Here is what I am testing. The three calls to swrite.writer work. The state of the device I am communicating with changes in accordance to what would be expected when the messages are received. There is no response. As always, guidance is appreciated. The program:# Test of uasyncio stream I/O using UART # Author: Peter Hinch # Copyright Peter Hinch 2017-2022 Released under the MIT license # Link X1 and X2 to test. import uasyncio as asyncio from machine import UART uart = UART(2, 9600, timeout=0) # these are TX2(GPIO17) and RX2(GPIO16) async def sender(): swriter = asyncio.StreamWriter(uart, {}) print('started sender loop') while True: ascii = "find\r" print(f'writing >>>{ascii}<<<\n ') swriter.write(ascii) await swriter.drain() await asyncio.sleep(10) ascii = 'X' print(f'writing >>>{ascii}<<<\n ') swriter.write(ascii) await swriter.drain() await asyncio.sleep(10) ascii = "c,1\r" print(f'writing >>>{ascii}<<<\n ') swriter.write(ascii) await swriter.drain() await asyncio.sleep(10) async def receiver(): sreader = asyncio.StreamReader(uart) print('started receiver loop') while True: print('waiting on receive') res = await sreader.readline() print('Received', res) async def main(): asyncio.create_task(sender()) asyncio.create_task(receiver()) while True: await asyncio.sleep(1) def test(): try: asyncio.run(main()) except KeyboardInterrupt: print('Interrupted') finally: asyncio.new_event_loop() print('as_demos.auart.test() to run again.') test() # The table below specifies the RX and TX pins for each of the three UART ports available in ESP32. # UART TX/RX Rx Tx Useable # UART0 0 GPIO3 GPIO1 Yes # UART1 GPIO9 GPIO10 Yes but requires the reassignment of pins # UART2 2 GPIO16 GPIO17 Yes The log produced: MPY: soft reboot started sender loop <<<ting >>>find started receiver loop waiting on receive writing >>>X<<< <<<ting >>>c,1 <<<ting >>>find writing >>>X<<< Interrupted

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On Wed, Feb 15, 2023 at 6:24 AM Peter Hinch ***@***.***> wrote: Also here <https://github.com/peterhinch/micropython-async/blob/master/v3/docs/TUTORIAL.md#63-using-the-stream-mechanism> . — Reply to this email directly, view it on GitHub <#10753 (reply in thread)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AEVW4EOWKFUHGHIFI2IAQ7DWXS4HJANCNFSM6AAAAAAU3X554Y> . You are receiving this because you authored the thread.Message ID: ***@***.*** com>

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[peterhinch]

The use of \r in your strings results in some odd printouts

<<<ting >>>find

which had me puzzled for a moment, but the code is behaving correctly.

I can see no reason for the receiver failing and I suspect a hardware problem. If you have access to a scope or LA I would check that data is actually being received. Alternatively do the classic loopback test: link txd and rxd and run the code: it should receive everything you send.