Soft Core (RTL IP) Enhanced UART with FIFOs & Synchronous CPU I/F

The Sibridge Technologies SI-M16550S core provides a fully programmable UART that is functionally compatible with the NS 16550AF device.

Like the NS 16550AF, the SI-M16550S supports transmission in word lengths of from five to eight bits, together with an optional parity bit and 1, 1½ or 2 stop bits. It also includes two 16-byte FIFOs – one for transmit and one for receive, a 16-bit programmable baud rate generator, an 8-bit scratch register and two DMA handshake lines, which may be configured either to support single-byte transfers (DMA Mode 0) or multiple-byte transfers (DMA Mode 1).

Unlike the NS 16550AF, the SI-M16550S offers a synchronous CPU interface. This interface is compatible with the Peripheral Virtual Component Interface (PVCI) defined by VSIA and so allows the core to be readily interfaced to a range of popular on-chip buses such as the AMBA bus and the buses associated with the IBM CoreConnect™ architecture.

The SI-M16550S also includes eight modem control lines and a diagnostic loop- back mode. Interrupts can be generated for a range of TX Buffer/FIFO, RX Buffer/FIFO, Modem Status and Line Status conditions.


  • Verilog Source code with lint checking
  • Verilog functional testbench and associated documentation
  • Design documentation