What changes should be done to enable FF on PIC18F26Q10?

[Amt]

Hi,
Could you help guide me again on what things should be modified to enable FF on this chip:
1. What header file should I start with? (also curious why)
2. How do I set the flash size? (I remember being told to subtract the SFR range from the total flash size but the pre existing headers don't match this calculation)

regards,
LeS

[Mikael Nordman]

These Q10 chips are a bitch to include.
They have an architecture that is a mix if traditional PIC18 and K42/K83 series and Q41/43 series and maybe some other differences.
So I did not bother to include support.

But if you want to learn a lot you can try.

This is the device header file
/opt/microchip/xc8/v2.35/pic/include/proc/pic18f26q10.h

This can be added to p18fxxxx.h.

#ifdef __18F26Q10
    #include "p18fxxq10.inc"
    #define PICTYPE PIC18F26Q10
    #define FLASH_LO  0x0000
    #define FLASH_HI  0xebff
    #define EEPROM_LO 0xec00
    #define EEPROM_HI 0xefff
    #define RAM_LO    0xf000
    #define RAM_HI    0xfcff
    #define FBUFFER   0xfd00   
    #undef  _FLASH_ERASE_SIZE
    #define _FLASH_ERASE_SIZE 0x100
    #define EEPROM_ADDRU 0x31
    #define EEPROM_MASKH 0x01
#endif

Attached a first version of the p18f26q10.inc file

[Amt]

Thanks! will experiment with this soon. I'm trying to standardize on a one PIC device so got curious about a few things:

1. What aspects of the K42 and Q41 series affect FF operations? I noticed a difference in the flash erase size. Other than not having EEPROM, shouldn't any PIC18 with flash > 8KB work ?

2. What pic18 chips work best for FF? and I'm curious why.

3. How about pic24 vs pic18 when it comes to FF? which one is better supported? or are there any caveats ?

[Mikael Nordman]

What aspects of the K42 and Q41 series affect FF operations? 
I noticed a difference in the flash erase size. 
Other than not having EEPROM, shouldn't any PIC18 with flash > 8KB work ?

When you check the #ifdefs in the source code you can see the differences between chips.
In practice you need at least 16 Kb. FF in itself uses 10 Kb + 2 Kb for the USB support.
All the supported PIC18 chips have EEPROM.

What pic18 chips work best for FF? and I'm curious why.

The supported chips are listed on the flashforth.com website. They all work.
I would recommend the 25K50 for USB support, 26K83 for CAN support or the 26K42 for general use.
The older chips, if available, have a little simpler peripherals, and thus easier to use.

How about pic24 vs pic18 when it comes to FF? 
which one is better supported? or are there any caveats ?

PIC18 is easier to interface in 5 volt systems, most PIC24 chips are 3.3 V.
PIC24 is faster.
In practice I mostly use PIC18 chips because of the peripherals and the 5V operation.