44
Utilities
4.8
Hot (Serial) Cable
To convert a standard serial cable to a Hot Cable, certain pins must be shorted together at the
Serial port header or at the DB9 connector. Short together the RTS (4) and RI (8) pins on either
the COM1 or COM2 (CN14 or CN16) header. As an alternate, you can short the equivalent pins
(pins 7 and 9) on the back of the respective DB9 connector as shown in the following figure.
4.9
Watchdog Timer
The Watchdog Timer (WDT) restarts the system if an error or mishap occurs, allowing the sys-
tem to recover from the mishap, even though the error condition may still exist. Possible prob-
lems include failure to boot properly, loss of control by the application software, failure of an
interface device, unexpected conditions on the bus, or other hardware or software malfunctions.
The WDT is used through the SEMA during normal system operation. The following SEMA fea-
tures provide support for the WDT.
X
ADLINK SEMA provides an API for the WDT. The API tickles (resets) the WDT before the
timer expires, otherwise the system will be reset.
X
Watchdog Code examples – ADLINK has provided source code examples in the
CM1-86DX3 SEMA, illustrating how to control the WDT. The code examples can be easily
copied to your environment to compile and test, or to make any desired changes before
compiling. Refer to the SEMA Programming Guide by downloading the SEMA Utility from
the CM1-86DX3 web page.
CM1-86DX3_HotCable_a
5
4
3
2
1
9
8
7
6
Standard DB9 Serial
Port Connector (Female)
Rear View
(or Front View of
Male Connector)
Or
1
3
5
7
9
2
4
6
8
10
Serial Port Header
(COM1 or COM2)