CCS C Software and Maintenance Offers
FAQFAQ   FAQForum Help   FAQOfficial CCS Support   SearchSearch  RegisterRegister 

ProfileProfile   Log in to check your private messagesLog in to check your private messages   Log inLog in 

CCS does not monitor this forum on a regular basis.

Please do not post bug reports on this forum. Send them to support@ccsinfo.com

rs232_errors+BIT6

 
Post new topic   Reply to topic    CCS Forum Index -> General CCS C Discussion
View previous topic :: View next topic  
Author Message
simon630



Joined: 07 Sep 2003
Posts: 17

View user's profile Send private message

rs232_errors+BIT6
PostPosted: Mon Mar 10, 2003 4:21 am     Reply with quote

dear gurus,
referring to page 45 of PCB,PCM, and PCW PICC Compiler reference manual, when Bit 6 of rs232_errors variable is set to one, it indicates a put failed in float high mode. could anybody explain what happen and how to resolve? thx in advance.
___________________________
This message was ported from CCS's old forum
Original Post ID: 12484
PCM programmer



Joined: 06 Sep 2003
Posts: 21708

View user's profile Send private message

Re: rs232_errors+BIT6
PostPosted: Mon Mar 10, 2003 1:24 pm     Reply with quote

:=dear gurus,
:=referring to page 45 of PCB,PCM, and PCW PICC Compiler reference manual, when Bit 6 of rs232_errors variable is set to one, it indicates a put failed in float high mode. could anybody explain what happen and how to resolve? thx in advance.
-----------------------------------------------------

That directive is an option for the #use rs232 statement.
It's only used in two CCS example files: ex_pbusm.c and ex_pbusr.c

Those examples show how to make a small one-wire "network"
between two or more PICs. There is a schematic in the
manual, and in the FAQ which shows the connections:
<a href="http://www.ccsinfo.com/faq/?23" TARGET="_blank">http://www.ccsinfo.com/faq/?23</a>
It consists of one wire between Pin B0 on several PICs and
one pull-up resistor. (Of course, there is also a Ground wire).

So a high level is created by the pull-up resistor. The PICs
do not drive pin B0 high. When they want to put out a high
level, they make pin B0 into an input (with the TRIS_B
register), and let the pull-up resistor pull the logic level
up to a high level. CCS calls this "float high". It just
means letting the pull-up resistor take the signal high,
rather than having the PIC drive it high.
___________________________
This message was ported from CCS's old forum
Original Post ID: 12500
Sherpa Doug
Guest







Re: rs232_errors+BIT6
PostPosted: Mon Mar 10, 2003 1:52 pm     Reply with quote

:=:=dear gurus,
:=:=referring to page 45 of PCB,PCM, and PCW PICC Compiler reference manual, when Bit 6 of rs232_errors variable is set to one, it indicates a put failed in float high mode. could anybody explain what happen and how to resolve? thx in advance.
:=-----------------------------------------------------
:=
:=That directive is an option for the #use rs232 statement.
:=It's only used in two CCS example files: ex_pbusm.c and ex_pbusr.c
:=
:=Those examples show how to make a small one-wire "network"
:=between two or more PICs. There is a schematic in the
:=manual, and in the FAQ which shows the connections:
:= <a href="http://www.ccsinfo.com/faq/?23" TARGET="_blank"> <a href="http://www.ccsinfo.com/faq/?23" TARGET="_blank">http://www.ccsinfo.com/faq/?23</a></a>
:=It consists of one wire between Pin B0 on several PICs and
:=one pull-up resistor. (Of course, there is also a Ground wire).
:=
:=So a high level is created by the pull-up resistor. The PICs
:=do not drive pin B0 high. When they want to put out a high
:=level, they make pin B0 into an input (with the TRIS_B
:=register), and let the pull-up resistor pull the logic level
:=up to a high level. CCS calls this "float high". It just
:=means letting the pull-up resistor take the signal high,
:=rather than having the PIC drive it high.

So if one accidentally got into "float high" mode, and did not have the pull-up resistor, you would get this error, because the non-existant resistor failed to pull the line high when no one else was pulling the line low.

If you have this problem I suggest you look at your #use RS232 statement and find out how you got into "float high" mode.

___________________________
This message was ported from CCS's old forum
Original Post ID: 12503
Display posts from previous:   
Post new topic   Reply to topic    CCS Forum Index -> General CCS C Discussion All times are GMT - 6 Hours
Page 1 of 1

 
Jump to:  
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum


Powered by phpBB © 2001, 2005 phpBB Group