fx-7000GA Main Chipset

The Casio fx-7000GA has an interesting and varied chipset. I found a memory chip by Sanyo and a microcontroller chip by NEC. All of these firms were at one time manufacturing IC technology for the calculator industry. Sanyo were the leaders in audio IC as well.

Microcontroller

The NEC D3050G IC handles the display and keyboard input. The blue coloured component is the resonator for generating the digital clock pulse. Just out of interest to see if it was possible to hack this calculator, I changed the resonator to a faster one to increase the speed and it worked! Now my calculator plots graphs a little faster.

Main Processor

The main processor is on a separate board and it performs all the mathematical functions.

Memory RAM

Sanyo LC3518BML-15 is a CMOS static RAM organised in 2048 words × 8 bits. Designed for the calculator market, it has an extremely low standby current consumption. If I can get some time and a replacement IC with more memory, I might hack this to increase the memory capacity. A hardware hack on this might be possible; however, the firmware on the microcontroller may require modification.

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