o. Is Microchip PIC32 Flash Programming Specification faulty?

PIC32 Flash Programming Specification codenamed 61145G (page 25, table 14-1) states that assembly instruction “lui $s3, 0xFF20” translates to 32-bit code “3C04BF80”, which is according to MIPS32 documentation not true. The code “3C04BF80” means “lui $a0, 0xBF80”. The mistake is somehow corrected in the Flash Programming Specification codenamed 61145L (page 30, table 14-1), where the CPU instruction code for “lui $s3, 0xFF20” is correct, “3C13FF20”. However, this is insufficient, because the instruction loads only the upper 16-bits of $a0 register. The lower 16-bits may still contain a random number, if the register was used before. If you want the piece of code from the table 14-1 to work correctly regardless of the initial state of the CPU before programming, you should add the instruction “ori $s3,$s3,0” (code: “36730000”) immediately after the instruction “lui $s3, 0xFF20”. This sets the lower 16 bits of the s3 register to 0 and corrects the problem.