Yet another computer museum - The Epson QX-10

The QX-10 came in several versions, with regional differences. The technical documentation mentions three regions, each having two versions:

U.S.A QX-10		Europe QX-10		Japan QC-10
HASCI version	ASCII version	Standard version	MultiFonts version	Standard version	Kanji version
128 kByte Video RAM	32 kByte Video RAM	32 kByte Video RAM		32 kByte Video RAM
256 kByte Main RAM	64 kByte Main RAM	64 kByte Main RAM	192 kByte Main RAM	32 kByte Main RAM	192 kByte Main RAM

The standard keyboard in the USA seems to be HASCII and in Europe some variations of ASCII.

Each region has its own version of the display character generator, so the extra-ASCII part (128-255) are different.

Upgrading to the maximum is easy, so lot of machines have more RAM.

Disk geometry

The standard disk geometry for the QX-10 is 16 sectors of 256 bytes per cylinder, 40 cylinders (tracks), double sided. Directory is on track 4, side 0.

The TPM-II system disks are different, having 10 512-byte sectors on track 2 and up. There is also a format of 512-byte sectors for all but Track 0, side 0.

The QX+ format introduced with the MML CP/M Plus, uses 5 sectors of 1024 bytes each, resulting in 400 kByte (minus the directory space). This format is not usable for system disks.

Operating systems

Rom dumps

All these are from an European MultiFonts QX-10
• Boot EPROM (disassembly with minimal comment)
• Two disassembled boot ROMs from Larry Green. Thanke Larry!
• Graphics card EPROM (Character generator) dump to text to make characters visible.
• MultiFonts Card Firmware EPROM (8039 controller)

Latest update: 2010-09-22

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