Category Archives: closed caption decoder

Kevin Timmerman sent me email about having built a USB version of the closed-caption decoder that Richard Ottosen and I developed.  He used an FTDI TTL-232R cable which incorporates a USB-to-serial interface chip.  He has added many new features to … Continue reading →

Got to work on the caption decoder a bit more today after all. It’s now basically working, though I may have to tweak the demodulation code a bit. Or maybe not; the errors we’re seeing may just be the result … Continue reading →

Spent most of the day working with Rich on the caption decoder again. Probably won’t get to work on it any more before I return to California. In the morning, Rich lugged his Tektronix 475A oscilliscope into the computer room, … Continue reading →

Worked on the new version of the caption decoder more over the last few days. Ripped out the old frame counter code, and put in a proper HH:MM:SS:FF counter, selectable for drop-frame or non-drop counting. Rich and I started trying … Continue reading →

The original concept for the new version of the closed-caption decoder was that everything would be interrupt-driven, and that there would be four interrupt sources: vertical sync from sync separator — would initialized timer 1 to count down horizontal lines … Continue reading →

I’m vacationing in Denver at the moment. Rich Ottosen and I are upgrading our closed-caption decoder to use a Microchip PIC16F627 rather than the PIC16C622 we previously used. The new chip has several advantages: flash memory — the PIC16C622 was … Continue reading →