View source for Talk:RPi Serial Connection
This page could do with some reorganisation but don't want to tread on toes. How about this page being dedicated to setting up and testing the serial port, and we do it by use-case. Windows/Linux terminal connection and Windows/Linux connection to a peripheral (including another computer).
- Step 1 in all cases is to decide whether or not one needs to disable the kernel boot messages.
- Step N-1 is testing with a bit of wire and a loop-back test.
- Step N is a set of links to how to access the port from a programming language
I have confirmed that this adapter [which adapter? can we remove this?] works with a synology TTL serial comm port. [] also confirmed the voltage is 3.3 from this convertor as loads of people were worried about degradation or failure using a 5v ttl serial convertor Waiting on the real thing to try it out.
Adafruit 954 USB serial cable
I been thinking of ordering the Adafruit 954 USB serial cable... but at the end I did not... the cable only costs $9.99 and the delivery $15.35... a bit of overkill? Could this cable not be ordered in Europe, or at least somewhere closer (cheaper) to Belgium?
- http://www.electroshopdendermonde.be (10 € ;same week delivery)
|Thread title||Replies||Last modified|
|USB serial connection to Raspian with systemd||0||16:36, 28 November 2017|
|Create a new page re: the manual configuration needed to prevent Linux from using the serial port||0||01:48, 20 May 2016|
|Glitch when serial port is opened||0||17:06, 25 July 2014|
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Create a new page re: the manual configuration needed to prevent Linux from using the serial port
I suggest to create a new page regarding the manual configuration needed to prevent Linux from using the serial port and place a link here because a) the text of that section is by far much longer than the other 2 methods b) almost everybody will use the other 2 methods and very-very few the manual one
When the serial port is opened there is a 32 us negative pulse on TXD (http://www.raspberrypi.org/forums/viewtopic.php?f=44&t=49867). Although many devices are error tolerant and thus not affected by this glitch, some are not and cannot easily be modified to deal with it. I would like to add a section to this page describing the glitch and how it can be avoided. It is difficult to search for information about this glitch. I did not find the linked forum post until I included 32us in the search string, and I only thought to measure the pulse because I was writing a new forum post myself. The glitch occurs when the serial port is opened, so the solution is to keep it open. This can be accomplished in bash with:
cat >/dev/ttyAMA0 &
If there are no objections I will add a small section on this glitch to this page in a few days.