ST MB1442, Руководство пользователя

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6.4.4 MCU power selection
JP1, VDD choice, selects the power supply of MCU in 3V3 or 5V:
•
3V3: Connect the jumper between pin 1 and 2 of JP1
• 5V: Connect the jumper between pin 2 and 3 of JP1
It is possible to measure the STM32 microcontroller consumption by removing the jumper and connecting an
ammeter:
•
Ammeter connected between [1-2]: power consumption measurement for VDD= 3V3
• Ammeter connected between [2-3]: power consumption measurement for VDD= 5V
6.5 LEDs
The tricolor LED (green, orange, red) LD1 (COM) provides information about ST-LINK communication status. The
LD1 default color is red. LD1 turns to green to indicate that the communication is in progress between the PC and
the ST-LINK/V2-1, with the following setup:
•
Slow blinking red/OFF: at power-on before USB initialization
• Fast blinking red/OFF: after the first correct communication between PC and ST-LINK/V2-1 (enumeration)
• Red ON: when initialization between PC and ST-LINK/V2-1 is completed
• Green ON: after a successful target communication initialization
• Blinking red/green: during communication with the target
• Green ON: communication finished and successful
• Orange ON: communication failure
User LD3: The green LED is a user LED connected to the CN4 connector pin 15 (D13).
•
When the I/O is HIGH value, the LED is ON
• When the I/O is LOW, the LED is OFF
PWR LD2: the red LED indicates that the STM8 part is powered and 5V power is available.
Default LD4: the red LED is a default LED connected to U2. It indicates that the current has exceeded the
expected limit.
6.6 Push-button
B1 RESET: the push-button is connected to NRST, and it is used to reset the STM8.
6.7 UART Virtual communication
Thanks to SB3 and SB4, the UART interface of STM8 available on PD5 (TX) and PD6 (RX), can be connected to
ST-LINK/V2-1. When UART Virtual communication is not used it is possible to use PD5/PD6 on ARDUINO
®
CN3
pins D1/D0. Refer to Table 6 .
Table 6. Virtual communication configuration
Solder bridge State
(1)
Description
SB3
ON UART virtual communication enabled
OFF No UART virtual communication
SB4
ON UART virtual communication enabled
OFF No UART virtual communication
1. The default configuration is reported in bold style.
UM2391
LEDs
UM2391 - Rev 1
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