SX Kid's Watch

william chan

I've been itching to make a Kid's game Watch based on the SX48 for some time.

But there are some hurdles to be overcome, like

1. Can SX48 directly interface to a COG LCD display directly? ( A very basic LCD glass without the HD44780 chipset)
Has anybody tried this before? At 3volts ? I heard from some sources that a small AC signal may be needed to directly control the LCD glass.

2. Since space is a major constraint, how to get rid of the 4 pin 0.1 inch programming header, yet make the SX reprogrammable?

3. If the SX48 runs on a 32.768 KHz clock crystal, how long can a 3V Lithium Coin battery last?

Thanks.

Jon Williams

1. I don't think so -- LCD multiplexing is a pretty specialized process (IO levels are not simply on/off)
2. Put some pads on your board and use "bed-of-nails" type pins
3. Depends on your other loads

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Jon Williams
Applications Engineer, Parallax