If you use DEFINE LOADER_USED 1, it will force PBP to start dropping code
at 0x04h, but it will always insert a GOTO INIT at 0x00h. The boot-loader
software normally just re maps this GOTO to a location after its own jump
vector.

If you're using LCDOUT or I2C, PBP will also insert CLRF FLAGS just before the
GOTO INIT, so that's something else to watch out for.