Looking for testers.... Jumentum BASIC language now has NTSC/PAL video output and PS/2 Keyboard input

03 Oct 2011


I have a new version of Jumentum-SOC (http://jumentum.sourceforge.net/) BASIC language development environment for the mbed to test. Jumentum-SOC is a BASIC language that allows rapid development of applications from a web browser, a text terminal, and now standalone using a television and attached keyboard.

The new version adds NTSC/PAL text output to a television screen using composite video. It is a 80x25 text screen that emulates a VT100 terminal. A PS/2 keyboard is also attached to act as a keyboard input. Therefore the MBED can operate as a standalone basic programmable computer like the Ye Olde Computers, except of course the LPC1768 is a single chip (and much faster too).

If anyone would like to test it I would appreciate it before releasing the version. I have included a screenshot of it running, a simple wiring diagram to hook up the keyboard and video screen, and binaries for NTSC and PAL video systems.

For the details of how it works... the video is streamed from the SSP0 port using DMA, with each scan line being composed on the fly. The RIT (repetitive interrupt timer) generates the 15 kHz sync signal, and the DMA interrupt prepares the next scan line for when the RIT interrupt is generated, so the DMA initiation and the sync signal are synchronized.

Any feedback you have would be appreciated. Thanks!


Here's a picture of it running:


Here is a wiring diagram of how to hook the MBED up


Here is a binary to test for NTSC


Here is a binary to test for PAL