Samsung's S3C4510B 16/32-bit RISC microcontroller is a cost-effective, high-performance microcontroller solution for Ethernet-based systems. An integrated Ethernet controller, the S3C4510B, is designed for use in managed communication hubs and routers. The S3C4510B is built around an outstanding CPU core: the 16/32-bit ARM7TDMI RISC processor designed by Advanced RISC Machines, Ltd. The ARM7TDMI core is a low-power, general purpose microprocessor macro-cell that was developed for use in application-specific and custom-specific integrated circuits. Its simple, elegant, and fully static design is particularly suitable for cost-sensitive and power-sensitive applications. The S3C4510B offers a configurable 8K-byte unified cache/SRAM and Ethernet controller which reduces total system cost. Most of the on-chip function blocks have been designed using an HDL synthesizer and the S3C4510B has been fully verified in Samsung's state-of-the-art ASIC test environment. Important peripheral functions include two HDLC channels with buffer descriptor, two UART channels, 2-channel GDMA, two 32-bit timers, and 18 programmable I/O ports. On-board logic includes an interrupt controller, DRAM/ SDRAM controller, and a controller for ROM/SRAM and flash memory. The System Manager includes an internal 32-bit system bus arbiter and an external memory controller.