Based on a WWW publication I found, I designed a software written in standard C for the MSP430 family. It can easily be modified for different micros.

The GA628 display provides a 12 character alphanumeric display , some icons in the second line and power consumption of some 100 uA. It can easily be connected to the hardware, simply by soldering some wires. The only disadvantage is , it needs a 3.3V power supply and something around 5.6V. However, this code and the MSP430 provides a clock for a simple charge pump, realized with 3 diodes and 3 capacitors.

Code
One may download the driver for the display here. (3K zipped)

Ericsson GA628 LCD display information
I2c device address: 0x74h, 0x75h
Lcd chip: PCF2103


1 = Vlcd (+5.6V)
2 = Gnd
3 = Vlogic (+2.8V)
4 = Vlogic (POR)
5 = Sdata (i2c)
6 = Sclk (i2c)

Charge pump schematic


Copyright 2006 Robert Tyrakowski