Synertek Systems KTM-2 & KTM-2/80

When I first saw the list price of the KTM-2/80, I thought it was a lot of money to put out for a keyboard and a handful of chips. That was before I saw what came for the money. Now, I think that it was the most cost effective terminal available, and that the price was unbelievably low for what you got. The -80 has two microprocessors, a 6502 and a 6507, two 6522 VIA's, 2 K of RAM and 6 K of ROM. It is a truly professional stand-alone terminal (capable of 9600 baud) that I attached to my SYM. The graphics capabilities, which are actually 160 by 48 (not 80 by 24), are an added bonus. Surplus monitors were available for around $50. Where else could get a terminal with all of the KTM-2/80 features for around $500.

General Description

The KTM-2 came in two models. The standard KTM-2 with its low video frequency (2.6MHz) can use ordinary home TV as a video monitor. This helped keep the user system cost low. The KTM-2/80 has twice the displayable characters; however it must be used with a video monitor since the 80 character lines have a higher frequency (7.2MHz). The KTM-2/80 is functionally identical in every respect with the KTM-2. Throughout the remainder of this article, KTM-2 will refer to both the KTM-2 and the KTM-2/80 unless otherwise noted.

The KTM-2 keyboard consists of 54 keys which generate 128 ASCII characters and 128 graphic characters. The ASCII characters include upper and lower case alpha, numeric, special and control. The graphic and alphanumeric characters can be displayed simultaneously. This is beneficial in business and industrial applications where annotated forms or graphs are desirable. With KTM-2's relative and absolute addressing, graphs, game pieces, etc, can be placed and/or moved about on the screen with a minimal amount of software.

The KTM-2 has two serial communications ports: the main port used primarily with a computer for information transfer and the auxiliary port used primarily with a printer for hard copy. The serial ports are full duplex allowing information to be transmitted and received simultaneously. The serial format is comprised of a start bit, seven data bits, a parity bit (for detection of transmission errors), and one or two stop bits. The bit transmission rate is selectable from 110 up to 9600 baud. The eight baud rates are selectable by three of the eight option switches. Other switch selectable features are: even, odd or no parity; interlaced or non-interlaced screen; line truncate or line wrap around (to next line); and 60Hz or 50Hz frame rate.

More Information about:


Upgrading a KTM2 to a KTM2-80

Upgrading the KTM System Boot ROM

Changing the Character ROM

Schematics, Manual & Binaries

Pictures of my homebuilt KTM