W78E052DDG is 8051 compatible 8-bit controller from Nuvoton with 8K programmable flash memory in 40 Pin DIP package. Wide operating voltage 2.4 – 5.5V, at 12 clock default per machine cycle it can achieve maximum 40 MHz and with 6T setting it can oparate at 20MHz. Peripheral includes Timer, counter, interrupt, watchdog timer and 4 ports and default configuration fully compatible with 80C52. This chip has separate dedicated 2K boot-loader memory, which makes this chip robust and very stable compare to other in this category. The chances of boot-loader erased or corrupted by user program or error are negligible. It supports ISP program downloading from PC using RX-TX lines only. Software for downloading is provided by the company free of cost.