CHPA SERIES
B-30
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B.16.1 Flash RAM - Operation and Programming
A Flash RAM is a memory device with the two best characteristics of a disk drive - non-volatile
memory and read/write capability. In the CHPA, a Flash RAM contains the M&C system’s
program contents. Software upgrades are easy to install in a Flash RAM based CHPA because
the upgrade consists of connecting a PC to the CHPA, then executing a PC program. In about
two and half minutes the transfer is complete without the hassle of removing the CHPA’s cover.
To enhance the reliability of this approach, a backup version of the CHPA’s software exists in
an EPROM. This version is not updated (nor can it be via the auxiliary serial port) when the
Flash RAM contents are updated. If the Flash RAM contents are corrupted, the CHPA can use
the EPROM based program. Also, when the CHPA is powered up, the user may force the
CHPA to use the EPROM based program. To determine which program version is in use, look
at the Software Version menu item. If the letter F follows the software version number, the
CHPA is using the Flash RAM’s program. If the letter R follows the software version number,
the CHPA is using the EPROM’s program.
B.16.2 To Force the CHPA to Use EPROM Contents
To force the CHPA to use the EPROM’s program, start with the CHPA turned off. On the front
panel, simultaneously hold down the 1, 2, and 3 keys. Turn the CHPA on, wait about one
second, then release the keys. To determine which program version is in use, look at the
Software Version menu item. If the letter F follows the software version number, the CHPA is
using the Flash RAM’s program. If the letter R follows the software version number, the CHPA
is using the EPROM’s program.
Note: When the CHPA is forced to turn-on with the EPROM program, all the
users settiable parameter like the serial settings and trip points are set to
default. The user needs to go back and reset to the desired values.
B.16.3 Reprogramming the Flash RAM
To update the CHPA’s firmware, connect a PC (using either COM1 or COM2 serial ports) to the
Auxiliary serial port (J10). A loader program on the PC and an EPROM based loader program
in the CHPA work together to transfer new software into the Flash RAM. Use the following
procedure to re-program the Flash RAM:
1.
On the CHPA, press the MENU key until the display shows:
F P A C
:
2.
Enter the Flash Programming Access Code : 111111