Hardware layout and configuration
UM1537
18/52
Doc ID 023059 Rev 1
Note:
The bi-directional voltage translator is implemented on the SPI MOSI signal between the
STM32F051R8T6 and the LCD to support the 3-wire serial interface of the
AM240320LGTNQW-01H LCD panel. The direction of this voltage translator is controlled by
IO PB2 (the IO PA7 acts as MOSI when PB2 is high or as MISO when PB2 is LOW).
2.14 RF
E2PROM
An RF E2PROM module ANT7-M24LR-A is mounted on connector CN2 and is connected to
the I2C1 bus of the STM32F051R8T6. It shares the same I2C1 bus as the temperature
sensor U8 and DDC on the HDMI_Source connector CN4.
2.15 HDMI
CEC
Two HDMI connectors CN3 and CN4 are available on the STM320518EVAL board.
●
Connector CN3 is an HDMI sink connector with:
–
DDC connected to I2C2 of the STM32F051R8T6
–
HPD controlled by I/O PA11 through transistor T3
–
CEC connected to PB10 through transistor T4
●
Connector CN4 is an HDMI source connector with:
–
DDC connected to I2C1 of the STM32F051R8T6 and shared with the temperature
sensor and RF E2PROM
–
HPD controlled by I/O PA8
–
CEC connected to PB10 through transistor T4
–
5V HDMI powered by power switch U5
Signals TDMS D+[0,1,2], T, TDMS D-[0,1,2] and TDMS_CLK are connected
together on these two HDMI connectors.
CEC injector mode can be enabled by reworking the PCB (for debugging purposes only):
●
Remove resistors R63, R66, R23, R62, R68, R51 and R13.
●
Close solder bridges SB4, SB5, SB6 and SB7.
Note:
The I/O PA11 must be set in open-drain output mode by firmware for HPD signal control on
the HDMI sink connector CN3.
6
RD
-
14
BL_Control
5 V
7
SDO
PB4
15
BL_GND
GND
8
RESET
RESET#
16
BL_GND
GND
Table 12.
LCD modules (continued)
2.4-inch TFT LCD connector CN16
Pin
Description
Pin connection
Pin
Description
Pin connection
