UM1775 Rev 4
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UM1775
Hardware layout
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The NFC board can be accessed in the SPI or UART mode.
6.6 Electronic
paper
display
(EPD)
The STM32L053 Discovery board includes an E-paper display with high contrast, high
reflectance and ultra-wide viewing angle.
This display is a TFT active matrix electrophoretic display. The 2.13" active area contains
122×250 pixels and it is capable to display images at 1-bit white, black full display
capabilities. An associated integrated circuit contains the buffers, interface, control logic,
oscillator, and DC-DC converter.
The STM32L053C8T6 controls this peripheral and is able to switch off its power supply.
6.7 JP4
(I
DD
)
Jumper JP4, labeled Idd, allows STM32L053C8T6 consumption direct measurement by a
module on board able to measure from 100 nA to 50 mA or by removing the jumper and
connecting an ammeter.
•
Jumper in position OFF: STM32L053C8T6 is powered (default).
Figure 9. Jumper JP4 in position OFF
Table 6. NFC connector pinout
CN1 pin
NFC signals
STM32L053C8T6
Description
1
NFC_IRQOUTN
or UART1_TX
PB7
Interrupt output for NFC connected to
STM32L053C8T6 UART1 RX
2
NFC_IRQINN or
UART1_RX
PB6
Interrupt input for CR95HF connected to
STM32L053C8T6 UART1 TX
3
NFC_NSS
PB12
SPI slave select
4
NFC_MISO
PB14
SPI data, slave output
5
NFC_MOSI
PB15
SPI data, slave input
6
NFC_SCK
PB13
SPI serial clock
7
+3V3
-
Main power supply/power supply for RF drivers
8
GND
-
Ground
