Video With the Propeller
I thought I'd show how video is generated with the Propeller as an example of multi-tasking and because video is cool.
Before we begin, let's review the tools we have to generate video: The Prop has no on-board peripherals except each core (a.k.a. cog) has 2 dedicated 'counter' modules (CTRA and CTRB) and a video generator (VCFG). This might sound crazy, but the Prop is fast enough to do stuff like 1-wire, i2c, UART, etc. in software. If you need UART, you just grab the UART object, and so on. Objects are available for tons of stuff.
The counter modules are 'set it and forget' and can be used to do:
By 'set it and forget it', I mean that you can tell each counter to do something (like synthesize a frequency or count pulses) and continue with your program. You can check back later and see how many pulses the counter counted, or stop / change the frequency being synthesized.
Here's the video circuit for the Propeller. You just need 3 resistors to generate video. I've connected them to p12,13,14 which is the most common pinouts for generating video.
Here's the entire program
MAKING IT MORE USEFUL
I usually use tv_text to display the value of variables, the status of an event, or simple menus. But it's up to you! TV_text uses almost no memory (3k) and is pretty flexible. There are other graphics libraries out there, too, for drawing charts, graphics, images and more.
Demo using the graphics object: