OLIMEX© 2015
STM32-P405 user's manual
6.4.4 R-T jumper
If you close this jumper RST and TRST at the JTAG will be connected together.
The default position of jumper R-T: open.6.4.4 CNTRL/HS
The RS pin (pin 8) on the SN65HVD230 provides three different modes of operation: high speed mode,
slope control mode, and low-power mode. CNTRL/HS jumper allows you to select a mode. The jumper
has three valid states – either both sides open; either the pads of CNTRL position connected; or the pads
of HS position connected. It is illegal to have both CNTRL pads soldered together and HS pads soldered
together. Each of the valid cases is described below:
•
Both sides of CNTRL/HS jumper open – 10kΩ resistor is connected to the control pin of
SN65HVD230 CAN driver – with a resistor value of 10kΩ the device will have a slew rate of ~15
V/μs
•
HS pads soldered together – high speed of output CAN drivers (>20v/uS) – no slope control
•
CNTRL/HS is connected to CNTRL side – enable PC10 (pin 51) of STM32F405 to control CAN
driver modes. Logical 1 of PC10 disables the CAN driver. Logical 0 of PC10 enables CAN driver
with high speed mode.
Refer to the documentation of SN65HVD230 for more information about different modes.
The default state of jumper CNTRL/HS: both sides open (slope control mode).
6.4.5 CAN0_T
Control whether there is a terminating resistor between the CAN buses. Closing the jumper connects
120Ω terminating resistor between CAN_L and CAN_H.
The default position of jumper CAN0_T: closed.
6.4.6 LED_E
Opening this jumper will disable the STAT LED.
The default position is closed.
6.4.7 USBP_E
Opening this jumper would disable the option to power the board from the USB connector.
The default position is closed.
6.4.8 WP_E jumper
Controls the write protect pin of the MMC card connector. If you disconnect this jumper the WP would be
disconnected from the SD/MMC card connector.
The default position of the jumper is closed – write protect pin (microcontroller pin #37 – PC6) is
available at the card connector.
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