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Test Pattern Generator

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Year released:
[www].se [ftp].se [mirror].us
TestPatternGenerator.img_.bin (462.25 KB)
MD5: 5380d9d6bc9987ed3464cf3d29668dfb
For System 1 - 5 - System 6.x
[www].se [ftp].se [mirror].us
TPG-128K.dsk_.bin (400.13 KB)
MD5: a43ac5908bfe909131318890976f6425
For System 1 - 5 - System 6.x
[www].se [ftp].se [mirror].us
TPG-512K.dsk_.bin (400.13 KB)
MD5: 74a43f4617be2d542cfa5e62c365c650
For System 1 - 5 - System 6.x
This app works with: Mini vMac Mini vMac II

Test Pattern Generator (or "TPG") was originally packaged on a 400k floppy diskette with Larry Pina’s book Macintosh Repair & Upgrade Secrets (Hayden Books, 1990). The software is intended for generating test patterns when calibrating the video and audio output of early Macs.

Two programs are included in TestPatternGenerator.img: "128k-TPG", for the original Macintosh, and "512k-TPG", for the Macintosh 512k or later.

The main difference between the two is that "128k-TPG" is specifically intended for the original Macintosh computer and its built-in 9-inch monitor, whilst "512k-TPG" can be adjusted to display test patterns for multiple different monitors, including custom models. Additionally, only "512k-TPG" can be used to produce test tones for audio calibration.

Special thanks to Jeff Walther (Trag) and tt for imaging and archiving this software. It was previously available on another website, but it has since gone down.

March 29, 2020 UPDATE: Added TPG-128k.dsk & TPG-512k.dsk because the *.img file does not work as is with Mini vMac. Jeff Walther kindly provided the original files this week, which enabled creation of these DSK files. The DSK files boot Mini vMac and are confirmed to work on an actual Macintosh 128K and 512K computer too. They are MacBinary encoded, so to use them with Mini vMac, just decode them, then use the DSK file. —JDW

Architecture: 68k

TPG is intended for use with early Macs such as the 128k, 512k, Plus, and SE, as well as the Macintosh XL (Lisa 2). However, 512k-TPG has been tested to run correctly on a Macintosh LCIII with VGA output running System 7.5.5, and tested on a Macintosh 512k with 64K ROMs, and may run fine on other models and system versions that are capable of running 68k software. NOTE: TPG-512k.dsk includes Macintalk in the System Folder, but the program continues to issue regular beeps and does not use voice at all, for reasons unknown.