4.2 Badram and Badrom Directives

The MPASM __BADRAM and __BADROM directives along with the __MAXRAM and __MAXROM directives specifies file register address ranges that should be flagged as being invalid should they be used by code.

Suggested Replacement

There is no replacement for these directives.

Using the -mreserve driver option will restrict linker classes to the desired memory ranges. If you only use symbols defined in psects placed into those classes, invalid memory areas will be avoided.

The_RAMSIZE and _ROMSIZE preprocessor macros are also available and indicate the largest data and program memory space address available with the selected target device.

#define DEST 0x7D0
PSECT text,CLASS=code,reloc=2  ;for PIC18 devices
;for other devices: PSECT text,class=CODE,delta=2
storeIt:
  movlw 66
#if DEST > _ROMSIZE
#error "destination out of bounds"
#endif
  BANKSEL (DEST)
  movwf BANKMASK(DEST)
  return

Note: The manual masking of addresses used as instruction operands (for example using the BANKMASK() or PAGEMASK() macros or ANDing the operand with a mask) is not necessary when using the -Wl,--fixupoverflow option and any of the ignore, warn, or lstwarn arguments.