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+--- Thread: send bytearray over UART (/thread-43297.html)
send bytearray over UART - trix - Sep-27-2024
hello,
i thought that i post this question a half hour aggo, but i can not find it back ?
no problem i asked again:
i want to send a bytearray over UART, but i'm not verry succesfull so far.
problem is, how to fill uart.write() ?
you can see in the first part of my posted code, how i fill the array.
the 2e part is how i want to send it.
how i want to do it now is "byte by byte" but I think this is not the right method
can anybody tell me how i have to do this ?
thanks in advance.
if scanner_uart.any(): # is anything comming from the scanner ?
r15 = bytearray(230)
scanner_uart.readinto(r15)
print("r15",[byte for byte in r15])
#************** SEND DATA TO 2E PIC0 **********************************
MAX485.value(1) # 1 = write and 0 = read MAX485
for i in range (229):
byte_to_send = r15 [i]
scanner_uart.write(b'\byte_to_send') #
time.sleep_ms (1)
# print(r7[i])
MAX485.value(0) # 1 = write and 0 = read MAX485
RE: send bytearray over UART - Larz60+ - Sep-27-2024
note line 8, 1 is an integer 1, not 0x01 (bit 1), is this what you wanted?
what is the error you are getting?
RE: send bytearray over UART - trix - Sep-28-2024
line 8 is a digital output, i change the name of this output to make it more clear (it was not a good name
)
RE: send bytearray over UART - deanhystad - Sep-28-2024
I do not understand your code. What is this supposed to do?
if scanner_uart.any():I assume scanner_uart is a serial.Serial object, but serial.Serial objects don't have a method named "any".
Why do you do this?
r15 = bytearray(230) scanner_uart.readinto(r15)instead of this?
r15 = scanner_uart.read(230)And why do this:
for i in range (229):
byte_to_send = r15 [i:i+1] # Needs to be bytes, not int
scanner_uart.write(byte_to_send)
time.sleep_ms (1)Instead of:scanner_uart.write(r15[:229])Is the 1 ms wait important?
RE: send bytearray over UART - trix - Sep-29-2024
(Sep-28-2024, 11:31 AM)deanhystad Wrote: I do not understand your code. What is this supposed to do?it waits till a mesage is comming on the UART
if scanner_uart.any():I assume scanner_uart is a serial.Serial object, but serial.Serial objects don't have a method named "any".
Quote:Why do you do this?i think that is the same, only write shorter
r15 = bytearray(230) scanner_uart.readinto(r15)instead of this?
r15 = scanner_uart.read(230)
Quote:And why do this:i think also it is the same but shorter, but shorter is simpler so better (but sometimes it doesn't become any easier to read).
for i in range (229): byte_to_send = r15 [i:i+1] # Needs to be bytes, not int scanner_uart.write(byte_to_send) time.sleep_ms (1)Instead of:
scanner_uart.write(r15[:229])Is the 1 ms wait important?
the 1 mSec. was just for test some things, maybey i don't need this.
RE: send bytearray over UART - deanhystad - Sep-29-2024
Are you using micropython? That is the only place I can find deinit() and any() for something related to uarts.
The micropython documentation says this about deinit()
Quote:You will not be able to call init() on the object after deinit(). A new instance needs to be created in that case.But I don't think you need to deinit the uart. This thread discusses changing the pins attached to the uart bus.
https://github.com/orgs/micropython/discussions/11506
RE: send bytearray over UART - trix - Sep-29-2024
indeed micro python, but I thought that was clear, am I in the wrong section?
RE: send bytearray over UART - deanhystad - Sep-30-2024
In this thread you did not mention you are using micropython. That would be a good thing to mention next time. I found out you are using raspberry pi pico from reading this post:
https://python-forum.io/thread-43303-post-181814.html#pid181814
And my response here, about remapping the UART to different pins, is a response to that post.
So if you want to read about remapping your UART to different pins, go look at this discussion:
https://github.com/orgs/micropython/discussions/11506
RE: send bytearray over UART - DeaD_EyE - Sep-30-2024
@micropython
from machine import UART
uart = UART(1, rx=..., tx=..., baudrate=...)
send_buffer = bytearray(b"Hello World\r\n")
bytes_sent = uart.write(send_buffer)
print(f"{bytes_sent} bytes were sent over serial")The return value of uart.write: https://docs.micropython.org/en/latest/library/machine.UART.html#machine.UART.write
RE: send bytearray over UART - trix - Sep-30-2024
sorry for the misunderstanding
, and thanks for the link. I'll take a good look at that.