[Coco] RSDOS TRACEON

Robert Gault robert.gault at worldnet.att.net
Fri Apr 9 23:17:24 EDT 2004


mmarlett at isd.net wrote:
> I have a customer that has lost their Internet connection due to a virus
> and has to reinstall.
> 
> She asked me to post a message to the list in hopes of a solution.
> 
> She writes code in DECB and when she is debugging she uses the TRACEON
> command. Her problem is that it scrolls by so fast that she can't use it's
> output very well. Is there a way to have that output go to a printer?
> 
> TIA,
> 
> Mark
> 

You have already gotten some suggestions on this problem. The specific 
code which handles TRON/TROFF is in Extended Basic and the relevant 
section follows:
version 2.0
$82DE	LDA	TRCFLG	TEST THE TRACE FLAG
	BEQ	$82F1	BRANCH IF TRACE OFF
	LDA	#$5B	< LEFT HAND MARKER FOR TRON LINE NUMBER
	JSR	>PUTCHR	OUTPUT A CHARACTER
	LDA	CURLIN	GET MS BYTE OF LINE NUMBER
	JSR	LBDCC	CONVERT ACCD TO DECIMAL AND PRINT TO CONSOLE OUT
	LDA	#$5D	> RIGHT MARKER FOR LINE NUMBER
	JSR	>PUTCHR
$82F1	JSR	GETNCH	GET NEXT CHARACTER FROM BASIC

There is nothing in these routines which will change the console out 
pointer. That means the TRON output will go to anything the console is 
set for. Having this on during tape or disk I/O does not look like a 
very good idea.

Depending on the program in question, the console device number at $6F 
could be set to printer for the trace and then reset to what is needed 
for the program.

In general, TRON is a terrible method for trouble shooting a program. 
Why don't you ask your friend what she is attempting to correct? This 
group could provide much better methods for tracking down the source of 
the problem.




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