The Kc89c72 is a CMOS, 8-bit microcontroller with 72 kilobytes of non-volatile memory , operating at 12–24 MHz, with 256 bytes of internal RAM, four 8-bit I/O ports, and standard 8051 peripherals.
Per the “Revision History” section of the Kc89c72 datasheet, engineers should note: Kc89c72 Datasheet
Using a standard EPROM programmer with a 40-pin ZIF socket. Algorithm: The Kc89c72 is a CMOS, 8-bit microcontroller with
| Pin | Symbol | Function | | :--- | :--- | :--- | | 1-8 | P1.0–P1.7 | Port 1 – General purpose I/O (also analog comparator inputs in some variants). | | 9 | RST | Reset input – high for two machine cycles to reset. | | 10-17 | P3.0–P3.7 | Port 3 – Alternate functions: RxD, TxD, INT0, INT1, T0, T1, WR, RD. | | 18-19 | XTAL2, XTAL1 | Crystal oscillator pins (12 MHz typical). | | 20 | VSS | Ground (0V). | | 21-28 | P2.0–P2.7 | Port 2 – General I/O or high-order address bus for external memory. | | 29 | PSEN | Program Store Enable – Reads external program memory. | | 30 | ALE/PROG | Address Latch Enable (or programming pulse during flash write). | | 31 | EA/VPP | External Access enable (tie to VCC to use internal flash; tie to GND for external ROM). VPP = programming voltage (12.5V). | | 32-39 | P0.0–P0.7 | Port 0 – Multiplexed low-order address/data bus (open drain). | | 40 | VCC | Main supply (+5V or +3.3V for low-voltage version). | | | 9 | RST | Reset input