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This object is provided under license. By downloading this object, you are agreeing to the terms of the MIT License.

Simple Serial

Bit-bang serial driver for low baud rate (~19.2K) devices.
* This driver is designed to be method-compatible with the FullDuplex serial object, allowing it to be used when high speed comms or devoting an independent cog for serial I/O is not necessary.
* Bi-directional communication on the same pin is also supported.

v1.3 - May 7, 2009 - Updated to fix rx method bug where uninitialized variable would mangle received byte.

 Version:
  1.3

Attributes:


Author:
  Chip Gracey (Parallax)

Categories:
  Protocol

Downloads:
  2,563

Last Updated:
  2009-05-15


User Reviews:
  • Michael Green commented:
    [Version 1.2] has a bug in the RX routine where the variable "b" is not initialized before use. To fix the bug, put a "b~" statement somewhere before the REPEAT loop.
    September 26, 2008 9:14 a.m.


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  • StefanL39 commented:
    My recomendation is to use the FullDuplexSerial-object and NOT simple_serial ! ----------------------------------------------- My Opinion about the simple_serial-object is: it is simple CODED but difficult to USE because of several limitations. ---- That's a quite hard judgement, but: - it is NOT possible to send and receive at the SAME time ----- - multiple byte-receiving is difficult: ---- - if you want to receive multiple bytes you can do nothing inbetween the receiving of the multiple bytes. ---- If you do something else inbetween there is a high danger that data gets partially lost ----- - if you use a loop that does check periodically for imcoming bytes, - inside this loop can be done not much more than that checking. ---- Otherwise there is the danger that data gets partially lost -------- - limited to a baudrate of 19200 baud -------------------------------------------------------------- Only in the case that you are running out of cogs (CoProcessors) it might be an option to use simple_serial as it does not need a cog for its own. --------------------------------------------------------------- My recomendation is to use the FullDuplexSerial-object This object needs a cog on its own but then you can - send and receive at the SAME time - receive up to 16 bytes in the background while your application does other things inclusive sending bytes - use higher baudrates up to 115200 baud. ------------------------------------------ Another tip is to take a look into the Extended_FullDuplexSerial-object it uses the FullDuplexSerial-object and adds methods to send and receive numbers and strings with and without timeouts regards Stefan
    May 26, 2008 4:04 p.m.


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