20
Pinouts and Signal Descriptions
3.3.12. SMBus
Signal
Pin
Description
I/O
PU/PD
Comment
SMB_CK B13
System Management Bus bidirectional clock
line. Power sourced through 5V standby rail
and main power rails.
I/O OD
3.3VSB
PU 8k2
3.3VSB
SMB_DAT# B14
System Management Bus bidirectional data
line. Power sourced through 5V standby rail
and main power rails.
I/O OD
3.3VSB
PU 8k2
3.3VSB
SMB_ALERT# B15 System Management Bus Alert – active low
input can be used to generate an SMI#
(System Management Interrupt) or to wake
the system. Power sourced through 5V
standby rail and main power rails.
I 3.3VSB
PU 10k
3.3VSB
3.3.13. I2C
Bus
Signal
Pin
Description
I/O
PU/PD
Comment
I2C_CK
B33
General purpose I²C port clock output/input
I/O OD
3.3VSB
PU 2k2
3.3VSB
Source SEMA BMC
or Braswell SoC as
alternative. (BMC by
default)
I2C_DAT
B34
General purpose I²C port data I/O line
I/O OD
3.3VSB
PU 2k2
3.3VSB
Source SEMA BMC
or Braswell SoC as
alternative. (BMC by
default)
3.3.14. General Purpose I/O (GPIO)
Signal
Pin
Description
I/O
PU/PD
Comment
GPO[0]
A93 General purpose output pins.
O 3.3V
PD 10k
After hardware
RESET output low
GPO[1]
B54 General purpose output pins.
O 3.3V
PD 10k
After hardware
RESET output low
GPO[2]
B57 General purpose output pins.
O 3.3V
PD 10k
After hardware
RESET output low
GPO[3]
B63 General purpose output pins.
O 3.3V
PD 10k
After hardware
RESET output low
GPI[0] A54
General purpose input pins.
Pulled high internally on the module.
I 3.3V
PU 10k 3.3V
GPI[1] A63
General purpose input pins.
Pulled high internally on the module.
I 3.3V
PU 10k 3.3V
GPI[2] A67
General purpose input pins.
Pulled high internally on the module.
I 3.3V
PU 10k 3.3V
GPI[3] A85
General purpose input pins.
Pulled high internally on the module.
I 3.3V
PU 10k 3.3V
Notes:
GPO[0:3], PU 10k 3.3V is by build option for programming these pins to be GPI.
GPI[0:3], PD 10k is by build option for programming these pins to be GPO.
cExpress-AL supports an SD/GPIO muxed design, controlled by BIOS setting. See the table below for pin
mapping.
Summary of Contents for cExpress-AL
Page 8: ...2 Introduction This page intentionally left blank ...
Page 36: ...30 Pinouts and Signal Descriptions This page intentionally left blank ...
Page 44: ...38 Module Interfaces This page intentionally left blank ...
Page 48: ...42 Smart Embedded Management Agent SEMA This page intentionally left blank ...
Page 88: ...82 BIOS Setup This page intentionally left blank ...
Page 98: ...92 BIOS Checkpoints Beep Codes This page intentionally left blank ...