UM0470 datasheet(13/37 Pages) STMICROELECTRONICS

部件名	UM0470

功能描述	STM8 SWIM communication protocol and debug module

PDF	37 Pages

Scroll/Zoom	100%

制造商	STMICROELECTRONICS [STMicroelectronics]

网页	http://www.st.com

标志

13 / 37 page

UM0470

Single wire interface module (SWIM)

13/37

3.8

SWIM communication in Halt mode

To maintain the communication link with the debug host, the HSI oscillator remains on when

the MCU enters Halt mode. This means that halt mode power consumption measurements

have no meaning when the SWIM module is active.

The NO_ACCESS bit in the SWIM_CSR register is set when the system is in HALT, WFI or

readout protection mode. This means the bus is not accessible in this case.

The OSCOFF bit in the SWIM_CSR register is used to switch off the oscillator. In this case,

debug control is lost as long as the device is in Halt mode and the SWIM pin is high. The

only way to recover the debug control is to induce a falling edge on SWIM pin: this will re-

enable the HSI oscillator.

UM0470 数据表(PDF) 13 Page - STMicroelectronics