STM8S datasheet(327/467 Pages) STMICROELECTRONICS

Part #	STM8S

Description	STM8S Series and STM8AF Series 8-bit microcontrollers

PDF	467 Pages

Scroll/Zoom	100%

Manufacturer	STMICROELECTRONICS [STMicroelectronics]

Direct Link	http://www.st.com

Logo

327 / 467 page

DocID14587 Rev 14

327/467

RM0016

Universal asynchronous receiver transmitter (UART)

377

22.3.1

UART character description

Word length may be selected as being either 8 or 9 bits by programming the M bit in the

UART_CR1 register (see Figure 114).

The UART_TX pin is in low state during the start bit. It is in high state during the stop bit.

An Idle character is interpreted as an entire frame of “1”s (the number of “1” ‘s includes the

start bit, the number of data bits and the number of stop bits).

A Break character is interpreted on receiving “0”s for a frame period. At the end of the

break frame the transmitter inserts either 1 or 2 stop bits (logic “1” bit) to acknowledge the

start bit.

Transmission and reception are driven by a common baud rate generator, the clock for each

is generated when the enable bit is set respectively for the transmitter and receiver.

The details of each block is given below.

Figure 114. Word length programming

STM8S Datasheet(PDF) 327 Page - STMicroelectronics