Four-bit single-chip microcontrollers with 4, 6, 8, 12, and 16KB of On-chip ROM Four-bit single-chip microcontrollers with 4 6 8 12 and 16 KB of On-chip ROM Four-bit single-chip microcontrollers with 6k and 8k of On-chip ROM Four-bit single-chip microcontroller with 16 KB of On-chip OTP PROM Four-bit single-chip microcontrollers with 4, 6, 8, 12, and 16 KB of On-chip ROM