NEC μPD7220

It was developed by Nippon Electric Company (NEC) in order to support the Kanji character set efficiently, which explains why the APC computer line had superior graphics compared to competing models.

[6] The N5200 sported a 5 MHz Intel 8086 processor on a 16-bit bus, and came with a text-only display board using a μPD7220 (in text mode).

In 1981, an English language paper written in 1980 by Tetsuji Oguchi, Misao Higuchi, Takashi Uno, Michiori Kamaya and Munekazu Suzuki was published in the IEEE.

[8] While most computers used memory mapped character, or bit-mapped displays, those with a μPD7220 had access to a, for the time, sophisticated graphics co-processor.

The large memory space, combined with hardware viewport registers permitted smooth high-speed scrolling.

In this way, bitmaps could be Blitted around the display at high speed and the controller kept focused on the more complex rendering tasks.

It included a light pen interface that synchronised the pixel clock to input signals without additional processor support.

A few years after its introduction, one journalist said "The 7220 GDC chip is a component that even some of NEC's competitors have found too good to pass up.