CX82100 Home Network Processor Data Sheet
2.3
Optional GPIO and Host Signal Usage
Optional GPIO and host signal usage is listed in Table 2-9.
Recommended GPIO signals are described in Table 2-10.
Table 2-9. CX82100 HNP Recommended GPIO and Host Signal Use
Pin Name
Pin
Default Use
Recommended Use
Signal Label
Reset
State
Notes
FCLKIO/GPIO39
BCLKIO/GPIO38
HAD31 (HCS4#)/GPIO37
HC00 (HCS0#)/GPIO32
GPIO31
GPIO27
GPIO26
GPIO25
GPIO24
USB_PWR_DET (GPIO22)
GPIO21
GPIO20
GPIO19
GPIO18
GPIO17
I2C_CLOCK (GPIO16)
I2C_DATA (GPIO15)
BOPT (GPIO14)
GPIO8
GPIO7
GPIO6
J1
J5
J8
GPIO39
GPIO38
HAD31 (HCS4#)
Z(pu)
Z(pu)
High
High
Z(pu)
Z(pu)
Z(pu)
Z(pu)
Z(pu)
Z
Z(pu)
Z(pu)
Z(pu)
Z(pu)
Low
Z(pu)
Z(pu)
Z(pu)
Low
Z(pu)
Z(pu)
Z(pu)
HCS4#:
HCS0#: Flash ROM CE#
5
2, 5
3
3
3
3
3
2, 6
3
3
3
3
3, 5
2
2
2
3, 5
3
3
3
P14 HC00 (HCS0#)
C6
G4
A8
M7
A1
C9
C3
B1
B2
A2
A3
E3
E2
K4
D5
E5
D6
E6
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
—
USB Power Detect
LAN 1 Reset
USB_PWR_DET
LAN1_RST#
Serial EEPROM Shift Clock
Serial EEPROM Data
Boot Loader Option
I2C_CLOCK
I2C_DATA
BOPT
Ready Indicator
LAN 2 Reset
LED_READY
LAN2_RST#
GPIO5
Notes:
1. Refer to applicable reference design information for exact GPIO use.
2. Recommended system use. See Table 2-2 for signal definition.
3. Recommended application use. See Table 2-4 for signal definition.
4. The Reset State column indicates the state of the pin upon power-on and whether or not it has an internal pullup. Z means a
high impedance state (an input) and pu/pd means the pin has an internal pullup/pulldown.
5. GPIOs that default to chip selects (GPIO32 and GPIO37), as well as GPIO8 and GPIO17, default to output upon power-on.
6. GPIO22 is the only GPIO that does not have an internal pullup/down, so if USB detect is important or used, GPIO22 should
be assigned to it. If GPIO22 is not used, or the firmware does not configure it to an output upon initialization, an external
pullup/down must be implemented on the board.
101306C
Conexant Proprietary and Confidential Information
2-19
CONEXANT [ CONEXANT SYSTEMS, INC ]
