UM1871 datasheet(14/64 Pages) STMICROELECTRONICS

14 / 64 page

Hardware layout and configuration

UM1871

14/64

DocID027604 Rev 3

2.4

Reset source

The reset signal of STM32446E-EVAL evaluation board is low active and the reset sources

include:

•

Reset button B1

•

DB_Connectors from CN13 pin 13

•

Embedded ST-LINK/V2-1

•

RS232 connector CN25 pin 8 (CTS) for ISP

Note:

The jumper JP5 should be set to control RESET by pin8 of RS232 connector CN25 (CTS

signal).

Table 2. 32 KHz crystal Y2 related solder bridges

Solder bridge

Description

SB108

PC14 is connected to 32KHz crystal when SB108 is open (default setting).

PC14 is connected to DB_CONNECTOR CN13 when SB108 is closed. In such case

SB43 must be removed to avoid disturbance due to the 32 KHz quartz.

SB107

PC15 is connected to 32KHz crystal when SB107 is open (default setting).

PC15 is connected to extension connector CN13 when SB107 is closed. In such

case SB56 must be removed to avoid disturbance due to the 32 KHz quartz.

Table 3. 8 MHz crystal Y4 related solder bridges

Solder bridge

Description

SB106

PH0 is connected to 8 MHz crystal when SB106 is open (default setting).

PH0 is connected to extension connector CN13 when SB106 is closed. In such case

SB69 must be removed to avoid disturbance due to the 32 KHz quartz.

SB105

PH1 is connected to 8 MHz crystal when SB105 is open (default setting).

PH1 is connected to extension connector CN26 when SB105 is closed. In such case

SB70 must be removed to avoid disturbance due to the 8 MHz quartz.

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