About the PIC24FK
In October 2009, initial support was added to the bootloader and code archive for the PIC24FK family (the bootloader and few of the chapter 8 examples have been tested on the 24F16K102). This is a low-power variant of the PIC24F family. Some notes on these devices:
- The C30 compiler defines the symbol __PIC24FK__ for this family so that you can distinguish it from the PIC24H, PIC24F processors.
- While this has the same clocking scheme as the PIC24F family, its configuration bits are like the PIC24H family (stored in separate memory locations, not on the last program page like PIC24F processors).
- The PIC24FK family has no 5V tolerant pins.
- The self-programming feature is different from PIC24H and PIC24F processors -- the PIC24FK can only erase a maximum of four rows of instructions at a time, and each row holds 32 instructions (by contrast, the PIC24H/24F can erase a page of memory at a time, where a page is 8 rows of 64 instructions). The NVMCOM register for the PIC24FK has been changed a bit to add additional erase options over those available in the PIC24H/24F family. If you are looking at the flash memory example in the code archive, be aware that this has not yet been modified to be compatible with the PIC24FK.
- While the 28-pin versions of the 24H (like the 24HJ32GP202) and the 24F (like the 24FJ64GA002) are pin-compatible with each other, the 28-pin PIC24FK (like the 24F16K102) is not pin compatible with these. The 24F16K102 does not have remappable pins, so all peripheral functions are assigned to fixed pin locations. This means that if you had a working 24HJ32GP202/24FJ64GA002 board, it is unlikely that board will work with the 24F16K102. When configuring pin functions for subsystems like the UART, you need to be careful to disable the analog pin functionality when dealing with these fixed pin locations.
- The PIC24FK does not have the VCAP/Vddcore pin of the PIC24H/F families (this pin required a low ESR 10 uF capacitor since as it was connected to the output of the on-chip voltage regulator).
- The comparator module of the PIC24FK looks to be much different from the comparator module of the PIC24F/H family (the comparator example code in the code archive has not yet been modified to be compatible with the PIC24FK).
- There are some new power saving tricks available on the PIC24FK, like a deep sleep watchdog timer.