Software Problems

[Tom Droege <tdroege@veriomail.com>]

Looks like I just sent the below to Arne when I meant to send it to the 
list.  Working on the problem a little more, it appears to be in the stamp 
code.  Some initialization problem causes the EPROM address bit to be 
set.  Sigh!  It will take a while to track it down.  This just emphasizes 
that all the code needs to be re-written by those more professional than I.

Thanks to your observation Arne, I have now localized this problem.  Not 
yet fixed, but fixing will be easy compared to finding it in the first 
place.  You may recall that the PROM program has two sections.  We only use 
the one in the low half of the memory.  I have caught the program switching 
to the high half program which has a quick erase in it.  This is no doubt 
software as the same register holds the analog multiplexer 
address.  Somewhere in all the calls I have put a 1 in the PROM program 
select position.  All calls should go through one sub but they do 
not.  Naughty me.  Now I will have to find the call and fix it.

To more clearly state the problem.  There is a register that is used to 
control a 32 - 1 selection of an analog multiplexer to rout the analog data 
to the ADC that is used for diagnostics.  The 5 low order bits of this 
register are used for the mux rout.  The high order bit is used to select 
which of two possible PROM programs are run.
It appears that somewhere after the scan is started, the mux is used 
(probably to read out a couple of temperatures) and left with a 1 in the 
high order position.  This causes the scanner to switch to the clear 
program.  Looks like the switch takes place after the block done has 
passed, or I did not put a block done in the clear program.  I have not 
tested it.

I think there are a few more things like this to be found.  Sigh!  I am now 
set up for it.  The first problem was getting the test set up working with 
the motors.  After a day of staring at the RA drive motor not working and 
checking everything, I finally gave up and changed out the Motor drive 
board.  When I did, I noticed a red tag which said "RA Drive Sick".

This to the public list to provide motivation to those working on the real 
time code.  There are lots of registers to be set right, and one needs to 
understand what each does.

Tom Droege

At 12:18 PM 9/12/00 -0700, you wrote:
Again, third night of ScnSky scanning, the system
has not missed any Block Done *except* that it
misses the clearing scan block done every time.
You should check this and see if it is a hardware
thing or a software initialization (important for
later software programs as well).
Arne