Table 41.
I2C_EXT connector pinout MB1262/CN13
Signal name
Pin
Pin
Signal name
EXT_SDA
1
2
NC
EXT_SCL
3
4
EXT_RST
3V3
5
6
NC
GND
7
8
NC
6.26
MFX MCU
The MFX, Multi-Function eXpander MCU, is used as a GPIO expander, in position MB1262/U20.
6.26.1
MFX I/O expander
Supplied by 3V3.
The communication interface between MFX and STM32MP157FAA1 is an I
2
C bus and IRQOUT pin.
The I
2
C is I2C2 that is shared with all the peripherals: audio codec, DSI LCD, RGB LTDC, camera, and USB Hub.
The MFX I
2
C address is 0x42h.
Table 42.
HW configuration for the MFX interface
I/O
SB
Setting
PI8
R127
ON
MFX_IRQ_OUT is connected to PI8
PH5
R124
ON
PH5 is used as I2C2_SDA
PH4
R125
ON
PH4 is used as I2C2_SCL
PD10
-
-
SUB_NRST
1. Default configuration in bold
Table 43.
I/O signals driven by the MFX
Pin number
Pin name
Signal name
Function
18
GPIO0
JOY_CENTER
MB1262/B1 joystick selection
19
GPIO1
JOY_DOWN
MB1262/B1 joystick down direction
20
GPIO2
JOY_LEFT
MB1262/B1 joystick left direction
39
GPIO3
JOY_RIGHT
MB1262/B1 joystick right direction
40
GPIO4
JOY_UP
MB1262/B1 joystick up direction
15
GPIO5
Audio_INT
MB1262/U8 audio codec interrupt
16
GPIO6
SMARTCARD_3V/5V
MB1262/U5 smartcard 3 V 5 V selection
17
GPIO7
SMARTCARD_OFF
MB1262/U5 smartcard OFF
29
GPIO8
SMARTCARD_RST
MB1262/U5 smartcard RESET
30
GPIO9
SMARTCARD_CMDVCC
MB1262/U5 smartcard VCC command
31
GPIO10
MIC_MEMS_LED
MB1262/CN8 pin12
32
GPIO11
-
-
33
GPIO12
CAMERA_PLUG
Camera plug detection
26
GPIO13
-
-
27
GPIO14
LCD_INT
DSI or LTDC interrupt
28
GPIO15
-
-
UM2648
MFX MCU
UM2648
-
Rev 1
page 37/61