
NXP Semiconductors.
8-bit 80C51 5 V low power 64 kB flash microcontroller with 1 kB RAM, SPI, 6-clock CPU with 6/12-clock peripherals

Philips Electronics
80C51 8-bit Flash microcontroller family 16KB/32KB/64KB ISP/IAP Flash with 512B/512B/1KB RAM

NXP Semiconductors.
8-bit 80C51 5 V low power 16/32/64 kB flash microcontroller with 1 kB RAM

NXP Semiconductors.
8-bit 80C51 5 V low power 16/32/64 kB flash microcontroller with 1 kB RAM