Lost communication

Questions on UARTs, and serial communication
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Posts: 845
Joined: Fri Oct 19, 2012 2:39 am
Location: Lake Tahoe, CA

Lost communication

Post by basicchip » Thu Sep 04, 2014 4:03 pm

>from a user
>Once I get a 'cannot communicate' popup - there doesn't seem to be any way to recover.
>I found it strange that I could toggle the RXD and get a display back, but the usual mbed Stop
>procedure wouldn't work, so sometimes I try to force a program download - and it fails also.
>[it may have startted to download and caused the reset/stop action from working -- I was
>forcing things so I understand/accept the failure - mainly just giving you FYI]

I too see this when swapping boards, mucking with reset or other odd things.

At some point Windows and/or the USB drivers get confused as to whether the port is open or not, and I have tried to find a programmatic work around, but there doesn't seem to be one for many cases.

I've found to get back in sync, yes you can exit the program and restart it (either BASICtools or TclTerm) or another way that often works is to disconnect the USB dongle from the PC (ie from the cable), then plug it back in and Options->Serial Ports->Refresh and then select the port often gets it up and running.

Posts: 316
Joined: Sat May 17, 2014 4:22 pm
Location: South Carolina

Re: Lost communication

Post by olzeke51 » Fri Sep 05, 2014 4:07 pm

FYII realize that I am doing something improper - but I kind of expected
the same results/feedback between the two chips mbed1768 & BasicChip
the fact that I got a comm error(on the mbed) -- maybe there is a clue for you
I don't expect you to error check the inputs -- but...they're different results
running program - it is asking for a menu input -- a number-- via debugin
I hit <Run button> with no value input, it defaults to 0 [which is default assigned]
they both are in a SELECT CASE // CASE 0 // STOP /....at this point in the program
'0' will cause it to STOP per program: I get the 'Coridium break message'
then if I input a 2 [one of my menu choices] AT the 'breakpoint' I get this
series of messages:
comm1a.JPG (32.61 KiB) Viewed 3210 times
so I clicked on "OK" and got this
comm1b.JPG (58.48 KiB) Viewed 3210 times
/// on the BasicChip I got this -- a different error number and no popup re: comm
/// and an attempt to load a {empty] program {WHICH it appears the mbed is trying to do ALSO]

choice was 0

Break: // notice it doesn't say Coridium break - understood - just FYI

@ hex [yy] - dump at hex yy words
! hex yy - write yy to hex
^ to run2 // nnotice the 2 is right next to the prompt- both chips
ERROR 3: Expected lvalue: variable, pointer, or register, found end of line
2 // my input a 2nd time
ERROR 3: Expected lvalue: variable, pointer, or register, found end of line
2 // my input a 3rd time
ERROR 3: Expected lvalue: variable, pointer, or register, found end of line

//// put in an empty line (ie just the <enter> key) NADA - just a LF on the screen
//// clicked on the <run> button and got thie ::
Programming Flash 1114...
ARMbasic[9.34g] on the PC Copyright 2014, Coridium Corp.
... ( 0.01K code + 0.00K const)/20K 0.00/2K data programmed
Just delete/modify this if I am off track/ causing unneeded issues

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