Compiler issues with PIC18F25J10

[Richard Arroyo]

Complier version 3.249 was useless programming the
25j10. The ICD-U40 gave an error message saying it couldn't detect the MCU.
In version 4.20 it programs fine put the MCU does nothing. The oscillator doesn't even run.
In noticed there are a few errors the Header file and device editor.
The 25j10 had 1536 bytes of ram not 1024.setup_oscillator() is useless among other things.
There appears to be a few configuration fuses missing.

Has anyone had any of these issues?

Well, I have to go to lunch with the CEO so more on this later.
_________________
RAA

[Richard A]

Ah ,1024 is correct. And timer 3 is defined. There is no timer 3 on this device.

[Richard Arroyo]

I have found the problem.
The ICD-U40 cannot program the j series processors correctly.
It doesn't set the configuration words correctly.
In fact, I think they are in the wrong location for this pic.
I used a different programmer and the pic runs fine.

I have noticed the ICD-U40 circuit board layout isn't the best. I could pick up noise up to 300Mhz on my spectrum analyzers 10 feet across the room
emitting form the U40. I had to install capacitors in the unit to keep it quiet.
_________________
RAA

[Ttelmah]

The configuration words on these chips are not stored at all in the way they are on the others. Basically, the configuration data is held in the last few locations of the main program memory. Then when the chip boots, it automatically copies this data to the normal configuration address, which is RAM, rather than ROM, and is writable during the boot up. This write is a 'hardware' function, and done automatically, before the code starts running. Once written, the data become read-only, till the next boot up.
You can use the chips, with 3.249, by writing the required configuration data into the program memory, using a #ROM statement. You can also program them with the ICD, the same way. However you can't run the 'ICD' functions, because the ICD code, overlays the memory area where the configuration data resides.

Best Wishes

[Richard Arroyo]

Hello, Ttelmah

Correct, I have found that in the data sheet though there are typo's and missing information as usual.
The device errata states to write the configuration bits starting at 7FF4h and not 300000h but the address is really
starts at 7FF8h. 300000h? lol

so #rom 0x7FF8 = {0b11110.... does the job.

I could not find the address for the OSCTUNE register in the data sheet to set the PLLEN bit.
It appears F9Bh is the correct address for the OSCTUNE register. I had to waste time finding it by programming the unimplemented registers.
Damn Microchip morons. The data sheet clames F9Bh is an unimplemented register.

The ICD-U40 still cannot program the j series processor correctly. Maybe it's because I updated the firmware
and introduced more bugs... bugware .
_________________
RAA

[Richard Arroyo]

Tell me if I am wrong but it appears the adcon registers are being set incorrectly according to the code.
Here is the output:

[PCM programmer]

[Richard A]

How could I be so blind.
I've always done it right in the past.
It must be the solder fumes.
I've been doing electronics
since the 1980's so maybe I have lead poisoning.


I'll correct it tomorrow.