4.6.1.10 Errata Option

The -merrata=type option allows specification of software workarounds to documented silicon errata issues. A default set of errata apply to each device, but this set can be adjusted by using this option and the arguments presented in the table below.

Table 4-12. Errata Workarounds
Type	#	Avoided Issue
`4000`	0	Program memory accesses/jumps across 4000h address boundary
`fastints`	1	Fast interrupt shadow registers corruption
`lfsr`	2	Broken LFSR instruction
`minus40`	3	Program memory reads at -40 degrees
`reset`	4	`goto` instruction cannot exist at Reset vector
`bsr15`	5	Flag problems when BSR holds value 15
`daw`	6	Broken DAW instruction
`eedatard`	7	Read EEDAT in immediate instruction after RD set
`eeadr`	8	Don't set RD bit immediately after loading EEADR
`ee_lvd`	9	LVD must stabilize before writing EEPROM
`fl_lvd`	10	LVD must stabilize before writing Flash
`tblwtint`	11	Clear interrupt registers before `tblwt` instruction
`fw4000`	12	Flash write exe must act on opposite side of 4000h boundary
`resetram`	13	RAM contents can corrupt if async. Reset occurs during write access
`fetch`	14	Corruptible instruction fetch. – applies FFFFh (`nop`) at required locations
`clocksw`	15	Code corruption if switching to external oscillator clock source – applies switch to HFINTOSC high-power mode first
`branch`	16	The PC might become invalid when restoring from an interrupt during a `bra` or `brw` instruction — avoids branch instructions
`brknop2`	17	Hardware breakpoints might be affected by `bra` instruction — avoids branching to the following location
`nvmreg`	18	The program will access data flash rather than program flash memory after a reset — adjusts the NVMCON register
`bsr63`	19	Corrupted execution of `movff` instruction when the BSR holds 63

At present, workarounds are mainly employed for PIC18 devices, but the clocksw and branch errata are only applicable for some enhanced Mid-range devices.

To disable all software workarounds, use the following.

-merrata=none

To maintain all the default workarounds but disable the jump across 4000 errata, for example, use the following:

-merrata=default,-4000

The value assigned to the preprocessor macro _ERRATA_TYPES (see Predefined Macros) indicates the errata applied. Each errata listed in Table 4-12 table represents one bit position in the macro’s value, with the topmost errata in the table being the least significant. That bit position in the _ERRATA_TYPES macro is set if the corresponding errata is applied. The header file <errata.h> contains definitions for each errata value, for example ERRATA_4000 and ERRATA_FETCH, which can be used with the compiler-defined _ERRATA_TYPES macro to determine which erratas are in effect.