Teslerpoint is a slide carousel system that displays bitmap images on the screen of an Apple Lisa computer. It comprises:

• teslerpoint.x68, a small program that runs on the Lisa's "bare metal" (i.e. without the presence of an operating system) and loads bitmaps directly from the hard drive to the video memory. See below for more information on how to use Teslerpoint on the Lisa.

• build_teslerpoint_presentation.py, a Python program that runs on a modern computer and assembles a collection of 720x364 image files into a bootable Teslerpoint hard drive image. An Apple Lisa booting from this hard drive image will boot directly into a Teslerpoint slide show that pages through the image files. This program contains its own binary copy of the assembled teslerpoint.x68 program. Refer to this program's --help text for more information.

Upon booting from a hard drive image (or even an actual hard drive if you arrange for this), Teslerpoint loads and displays the first bitmap. The user interface is minimal: press space, ., or the mouse button to advance to the next bitmap, b or , to go back to the previous bitmap, > to advance five bitmaps ahead, or < to go back five bitmaps. It's not possible to go beyond the last or first bitmaps. Press Q (note capital-Q) to quit to the ROM. Teslerpoint ignores the power button: if you wish to turn off the Lisa, quit to the ROM first and then press power.

The software utilities used to assemble teslerpoint.x68 include

• the EASy68k command-line assembler distributed by Ray Arachelian and
• the srec_cat utility from the srecord project,

The Makefile executes the step-by-step process of assembling a new teslerpoint.bin binary and using that to construct a test Teslerpoint slide show. You may need to edit the contents of the Makefile to specify the correct path to your copy of the EASy68k command-line assembler.

This program was written mostly off-the-cuff, but the usual (and sincere!) thanks goes out to documentation sites like Bitsavers and Ray Arachelian's Lisa documents collection, as well as the fine LisaList2 community.

teslerpoint.x68, build_teslerpoint_presentation.py, and any supporting programs, software libraries, and documentation distributed alongside them are released into the public domain without any warranty. See the LICENSE file for details.

11 June 2024: Initial release. (Tom Stepleton, [email protected], London)