18F46K22 being dyslexic

[Charles Linquis]

Darrel, I'm getting lamer and lazier every day. I have Proteus, but never got it to work with PBP. Do you have a 'quick-start' guide of some sort to get me started?

[Darrel Taylor]

Darrel, I'm getting lamer and lazier every day. I have Proteus, but never got it to work with PBP. Do you have a 'quick-start' guide of some sort to get me started?

Hi Charles,

I didn't, but I just recorded a simple demo that should get you going.
Unscripted, umms and sniffles included.

http://support.melabs.com/DT/Proteus...oteusDemo.html

[Charles Linquis]

Darrel,










Thanks! That got me going. Now I just have to learn to use Proteus' schematic capture. I normally use Altium.

Why didn't LabCenter do this? You should sell your efforts to them. And then you should do more on other topics.
Debugging/simulation in all its forms seems like fertile ground.

[comwarrior]

hi guys, thank you for the help...
yes tried port and lat alternates same results.

i wrote a test sequence to test all the IO pins sequentially... and i marked on the data sheet which pins were not doing what they were supposed to and then noticed a paturn.

I read the device registers for things like MSSP, EUSARTS, PWM etc etc and found that after a cold start these registers were not in the states they were supposed to be acording to the datasheet. So basically, their was hardware turned on that should be off that was taking control of the pins.
I modified the program to reset any register that wasn't in it's proper state. once i did this everything worked perfectly.
I went through the remains of the last batch of 46K22's (~15) and found that every single one had the same issue, but once the registers were reset they never had an issue.

So, thursday last week i sent a large email bug report to microchip detailing what was wrong and what it looks like that is the problem. I also included the chip batch numbers.
As of yet, i have only received the standard acknowledgement of email... which i find to be quite disappointing for such a large company.

I also searched micro-chips documentation and forums etc for any other report of this issue and i seem to be the first / the only one...
So, in the event someone else has a similar issue, this details how to diagnose it and then fix it.

EDIT:
It's a shame that PBP3 didn't come with a simulator... it was also quite disappointing.

[Darrel Taylor]

So which registers don't have the correct power-on value?

I don't have a 46K22 to look at.

[Dave]

Comwarrior, I have been watching this thread quite closly because I have been using the 18F46K22's for quite some time. I have never noticed a problem with them being "Dyslexic". However, I have never ASSUMED the state of ANY registers of ANY PIC's I have used in the past. How could you assume the state to be as printed in the documentation when there is nothing like a BIOS to set them after a power on sequence or a power disturbance. Poweron states are slightly better than random as far as I have seen in the past so I have ALWAYS set ALL register states after poweron or reset.... You should too..... Never assume anything...

[Darrel Taylor]

Dave,

No, All registers have a defined power-on state. And those states are clearly listed in the datasheet. There's nothing random about it.
I've never seen a chip power-up with in-correct states before, so i would like to see what comwarrior found.

People should NOT try to initialize every register at the beginning of the program.
This creates many more problems then it will ever solve, since most people will not bother to read the datasheet to find out what they should set them to.

comwarrior,
What revision is the datasheet you are using?