Chapter 3 Hardware
CoreModule 420 Reference Manual 41
Table 3-18. User GPIO Signals Pin/Signal Descriptions (J8)
Pin # Signal Description
1 GPIO8 User defined
2 GPIO9 User defined
3GPIO10User defined
4GPIO11User defined
5GPIO12User defined
6GPIO13User defined
7GPIO14User defined
8GPIO15User defined
9GND Ground
10 GND Ground
Notes: The shaded area denotes ground.
Oops! Jumper (BIOS Recovery)
The Oops! jumper is provided in the event you’ve selected BIOS settings that prevent you from booting
the system. By using the Oops! jumper you can stop the current BIOS settings in the CMOS from being
loaded, allowing you to proceed, using the default settings. Connect the DTR pin to the RI pin on Serial
port 1 (COM 1) prior to boot up to prevent the present BIOS settings from loading. After booting with
the Oops! jumper in place, remove the Oops! jumper and go into BIOS Setup.
To restore your BIOS setting changes without the erro rs, you must first select Load Factory Default
Settings, which will automatically load and save the defaults and reboot the system. Then you can
modify the default settings to your d esired values. Ensure you save the changes b efore rebooting the
system.
NOTE The CoreModule 420 Serial Port 1 (J3) is a 10-pin header and uses
pin 7 = DTR and pin 8 = RI. At Serial Port 1, short pin 7 to 8, as
shown in Figure 3-2. Alternatively, you may short the equivalent
pins on the DB9 connector attached to Serial Port 1 as shown in
Figure 3-2.
Serial Ports (J3, J9)
(COM1 or COM2)

1

2

3

4

5

6

7

8

9

10

Side View

Or

Standard DB9 Serial
Port Connector (Female)
Rear View
5
4
321
987
6
CM420serconjump
Figure 3-2. Oops! Jumper
Serial Console
The CM 420 BIOS supports the serial console (or console redirection) feature. These I/O functions are
provided by an ANSI-compatible serial terminal, or the equivalent terminal emulation software running
on another system. This can be very useful when setting up the BIOS on a production line for systems
that are not connected to a keyboard and display.