ROM resident function name	Entry address in ’QY4	Description
GETBYTE	$2800	Read 1 byte from PTA0
PUTBYTE	$FEA1	Send 1 byte out PTA0
RDVRRNG	$2803	Read and verify range of flash memory (send memory range out PTA0)
ERARNGE	$2806	Flash memory erase range
PRGRNGE	$2809	Flash memory program range

Table 2—With the ’QY4’s limited flash memory, these built-in ROM routines come in handy.