Raspberry Pi Forums

mmkw43

I have only used microcontrollers with RS232 in the past and never a problem but now trying to interface a PIC to the RPI3B. Some basic questions -- (1) What type of variable is it when you do a serial read? Is it a bytearray? In my code below that's what it looks like (picdata = ser.read(4) ) (2) I...

mmkw43

I'm using this. It's working fine although I'm sure the code be more compact. Is there an easy way to get LSB instead of MSB ? Thank you. try: ser = serial.Serial("/dev/serial0",baudrate=2400) except SerialException: pass picdata = ser.read(4) x = list(picdata) qone = (x[0]) qtwo = (x[1]) ...

mmkw43

Thanks -- and it seems also (through my playing with it) that I can simply -- var1 = (d[2]) d is the binary number in my code above var2 = (d[3]) etc? so in python you ignore bits 0 and 1 (b and 0) and the byte starts at [2] through [9] ? what is the option to get MSB or LSB ? I'll try and get 8 var...

mmkw43

Got my serial problem solved but stumped on how to look at each bit in a binary number. a = ser.read(4) b = list(a)) c = (b[2]) d = bin(c) and need to check d bits for set/not set and create 8 variables for the bits. spent 2 hours trying to learn how but can't find it. I believe it involves the bitw...

mmkw43

I see quite a few post and YT videos using this module with the pi but the max485 module is 5v only ?

mmkw43

I want to interface a 5v pic microcontroller between one of these ebay rs485 modules and the PI3 B. What Vss do you connect the module to? 5v or 3.3v? Obviously, I will have to connect to the 5v on the pic for the other module. Any issues? I know you have to keep 5v out of the Uart pins? THANKS. edi...

mmkw43

figured it out.
made some dumb moves.
serial in initialize? nope.

mmkw43

anyway -- I can't get anything to happen. class myClass: def __init__(self): ser = serial.Serial("/dev/serial0",baudrate=9600) def function(self): data = ser.readline() and I get a name error that ser is not defined. there's much more to the code but this is crazy -- from the examples I've...

mmkw43

Ok -- can't believe it. Started this today and simply did this -- ser = serial.Serial("/dev/ttyS0") is it ttyS0 or serialS0 ? ser.baudrate = 9600 and I put that in a class initialize (can I?) then I simply did this in a function that's in that class, picdata = ser.readline() and I get an e...

mmkw43

Ok thanks very much. That makes sense of course but these details need to be spelled out somewhere so you actually know what's going on. Plenty of other parts, (microcontrollers etc) always require a setup first and that's my mindset. edit -- I guess when you enable serial comm in raspi-config it fi...

mmkw43

Well, what I mean is how do you setup the pin? LIke GPIO.setup(10, GPIO.IN) to make an input But how to implement the Uart instead ? ! I spent all day trying to find this. Drove me nuts. You can't find anything anymore in searches. Take me back to 1992 and Alta Vista. I'm guessing it might be (10,RX...

mmkw43

For some reason, the world of search results has become absolutely useless in the past few years so I can't believe I'm asking this but -- how in the heck do you setup pins 8 and 10 to be assigned to the UART? I'll assume the default setup is GPIO. Even something as basic as this and all the links l...

mmkw43

dagnabit.

I missed that short introduction. Ok thanks fellas, I'm good to go now.
(We'll see).

mmkw43

Once again I'm trying to just get the basics about another aspect of python with dozens of ridiculous youtube videos and poor search results in an effort to just get the bare necessities s p e l l e d out. It would be so nice if the RPI pages had simple, short tutorials on the popular modules becaus...

mmkw43

I've never used a touchscreen at all and looking for a good basic understanding of HOW a pi would even communicate with one. I realize that on the models specific for the PI, there is a connection between the GPIO pins and the monitor, so that makes sense but how in the heck do you setup a conventio...

mmkw43

Thank you -- lesson learned. I didn't know what I was getting into. Thought it would be more straightforward and as easy as using pickle, which I've always done before.

mmkw43

Maybe I have the wrong impression about saving to a text file. I had several separate text files that were saving individual strings and thought I could consolidate them. (I've done it with pickle, so maybe I have to go back to that). I thought that I could save multiple strings and end up parsing t...

mmkw43

I thought I had it but honestly I'm thoroughly confused on this. The file writes fine one line at a time and I'm writing 8 strings. with open('all.txt','w') as fw: a = ck.get() fw.write(a+'\n') b = dg.get() fw.write(b+'\n') that writes it all fine but I can't figure out how to decipher each line to ...

mmkw43

var[0]
var[1] #figured it out and kicking myself

mmkw43

well, this is embarrassing as heck but I'm going in circles trying to get back one line at a time when I read a text file. I've really never used a text file for data other than a single line -- I used pickle for multiple items and that went smoothly. BIG THANKS. a = 'bob' b = 'roy' fw = open("...

mmkw43

well ships, I was under the impression it didn't need \n after all it's called writelines

mmkw43

I've always just used write() without a problem, never used writelines() Checked over and over again all I could find on it yet this writes everything to a single line in all.txt From what I understood, each string should be on a seperate line. What am I doing wrong? (!) The strings are right, just ...

mmkw43

Thanks much. I should have tried it a long time ago -- ran across raise() a long time ago but I think the wording in the docs really had me stumped.

mmkw43

I had asked about giving a widget "priority" a few different times here on the forum and walked away mystified that there wasn't a solution. So after all this time with my only real frustration about tkinter, it seems as easy as using tkraise(). I'm only posting this to confirm. I can simp...

mmkw43

Before I delve into pyarmor and the world of obfuscating, I wanted to ask just how easy is it to get accurate source code out of these decompilers I've read about ? Are they "that' effective? Or not worth the hassle for most? I read where they will ignore comments? I read briefly about a couple...

Search found 708 matches

Basic serial stuff

Re: Extract bits from binary?

Re: Extract bits from binary?

Extract bits from binary?

Re: RS485 module Vss ?

RS485 module Vss ?

Re: PI3 B uart setup

Re: PI3 B uart setup

Re: PI3 B uart setup

Re: PI3 B uart setup

Re: PI3 B uart setup

PI3 B uart setup

Re: Serial port basics

Serial port basics

Touchscreen tutorial

Re: Huh ? -- writelines()

Re: Huh ? -- writelines()

Re: Huh ? -- writelines()

Re: Huh ? -- writelines()

Re: Huh ? -- writelines()

Re: Huh ? -- writelines()

Huh ? -- writelines()

Re: tkraise() -- need confirmation

tkraise() -- need confirmation

Decompile PYC