Overview Of Uart; Table 12-1 Function Of Uart - Fujitsu MB90420/5 (A) Series Hardware Manual

This chapter explains the function and operation of the UART.

12.1 Overview of UART

The UART is a general-purpose serial-data communication interface for synchronous or asynchronous
communication (start-stop synchronization) with external devices. The UART has both normal bidirectional
communication (normal mode) and master/slave mode communication functions (This function is a
multiprocessor mode and is supported only by the master side).
n Function of UART
The UART is a general-purpose serial-data communication interface, which transmits/receives serial data
with other CPU or the peripheral unit.
Table 12-1 shows the function of UART.
Data buffer
Transfer mode
Baud rate
Data length
Signal type
Detection of receive-time error
Interrupt request
Master/slave communication
function (multiprocessor mode)
Note: At the clock synchronous transfer, the UART only transfers data, not affixing the start and stop bits.
UART

Table 12-1 Function of UART

Full-duplicate double-buffer
• Synchronous to clock (without start bit/stop bit).
• Asynchronous (start-stop synchronization) to clock
• Dedicated baud-rate generator (The baud rate can be selected from among eight
types.)
• Any baud rate can be set by external clock.
• Internal clock (An internal clock supplied from the 16-bit reload timer can be
used.)
• 7 bits (for asynchronous normal mode only)
• 8 bits
NRZ (Non Return to Zero) type
• Framing error
• Overrun error
• Parity error (Not supported for multiprocessor mode)
• Receive interrupt (completion of reception, detection of receive error)
• Transmit interrupt (completion of transmission)
• Both the transmission and reception conform to the EI
This function enables communications between 1 (master) and n (slave) (This
function is supported by only the master side).
12-3
Function
2
OS.