Instruction manual

ControlWave Gas Flow Computer (GFC Plus) Instruction Manual (CI-ControlWave GFC Plus)

Revised Feb-2013 Introduction 1-5

CPU Backup Battery

The CPU/System Controller board has a coin cell socket that accepts a

3.0V, 300 mA-hr lithium battery. This 3.0V battery provides backup

power for the real-time clock and the system’s Static RAM (SRAM).

CPU Memory

There are several different types of memory used by the CPU:

Boot/Downloader FLASH

Boot/download code is contained in a single 512 Kbyte FLASH chip.

Boot FLASH also holds the value of soft switches, audit/archive file

configurations, and user account and port information.

FLASH Memory

The ControlWave GFC Plus includes 8 MB of FLASH memory. The

FLASH memory holds the system firmware and the boot project.

Optionally FLASH memory also stores the zipped ControlWave project

(*.zwt), user files, and historical data (audit/archive files).The FLASH

does not support hardware write protection.

System Memory (SRAM)

The ControlWave GFC Plus has 2 MB of static random access memory

(SRAM). During power loss periods, SRAM enters data retention mode

(powered by a backup 3.0V lithium battery). Critical system information

that must be retained during power outages or when the system has been

disabled for maintenance is stored here. This includes the last states of

all I/O points, audit/archive historical data (if not stored in FLASH), the

values of any variables marked RETAIN, the values of any variables

assigned to the static memory area, and any pending alarm messages not

yet reported.

1.4 Power Options

You can power the ControlWave GFC Plus by: