VULCAN Technical Manual
Detailed hardware description
© 2007 Eurotech Ltd Issue D
18
IXP425 GPIO pin assignments
The following table summarises the use of the 16 IXP425 GPIO pins, their direction
and active level:
GPIO Signal name
Direction
Active
Function
See section…
0 RTC_RST# Output
RTC
reset
1 RTC_CLK Output
RTC
clock
, page
2 USB_INTA# Input Low
USB
3 CF_INTB# Input Low
CF
interrupt
4 UART_IRQ# Input Low
UART
interrupt
5
ISA_IRQ3
Input
Rising edge PC/104 interrupt
6
ISA_IRQ4
Input
Rising edge PC/104 interrupt
7
ISA_IRQ5
Input
Rising edge PC/104 interrupt
8
ISA_IRQ6
Input
Rising edge PC/104 interrupt
9
ISA_IRQ7
Input
Rising edge PC/104 interrupt
10
ISA_IRQ10
Input
Rising edge PC/104 interrupt
11
ISA_IRQ11
Input
Rising edge PC/104 interrupt
12
ISA_IRQ12
Input
Rising edge PC/104 interrupt
page
13 RTC_D
Bidirectional
RTC
data
, page
14
SER_NO
Bidirectional
Serial number
data
, page
15
GPIO_PCI_CLK Output
PCI clock 33MHz
, page
It is the responsibility of software to set up these GPIO port pins correctly.