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softex
01-20-2009, 04:14 AM
Hello all,

I have a rather large application running on a PIC 18LF2620 and would like to output text serial video strings to the propeller for video processing. There I figure to tweak the video software a bit to jazz up the text display - like double-sized (or larger) fonts, etc. Basically, I propose to use the propeller strictly as a composite text video driver for this PROTON BASIC app running on a PIC, instead of using my EZVid (www.multilabs.net (http://www.multilabs.net)) serial video generator add-on board (great product, but way too expensive for production). As ever, when it comes to this stuff, I know just enough to be dangerous - and no more. I can generally get results if pushed in the right direction so ... Has anybody here tried something like this? Or is it just a stupid idea? Any help/advice greatly appreciated.

-Dave

jazzed
01-20-2009, 04:35 AM
Someone got honorable mention in a Parallax contest for using Propeller as a peripheral device connected to a 6502.

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--Steve

Oldbitcollector (Jeff)
01-20-2009, 05:16 AM
Looking at the ezVID, you can almost do the same thing with the terminal software here (http://forums.parallax.com/showthread.php?p=772078).
(Grab the first download link. PropCOMM2_ascii)

The difference being that it doesn't handle text like a bitmap, but the display package
allows redefinition of characters on the fly, so basic graphics be created with the text.

It could be adapted easily for various display functions.

OBC

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New to the Propeller?

Check out: Protoboard Introduction (http://jeffledger.googlepages.com/Protoboard_Introduction.pdf) , Propeller Cookbook 1.4 (http://ucontroller.com/Propeller%20Protoboard%20Designs%20for%20the%20Beg inner.pdf) & Software Index (http://forums.parallax.com/showthread.php?p=770318)
Updates to the Cookbook are now posted to: Propeller.warrantyvoid.us (http://propeller.warrantyvoid.us)
Got an SD card connected? - PropDOS (http://www.orrtech.net/propdos/)

Leon
01-20-2009, 05:23 AM
A CPLD and RAM could be used, and might be cheaper.

Leon

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Amateur radio callsign: G1HSM
Suzuki SV1000S motorcycle

softex
01-20-2009, 07:02 AM
Thanks, I just got a proto board and havn't done much with it yet. From what I've read, I just might be able to manage to customize the spin code in the various driver variations that seem to be available, including the one mentioned above. If I come up with anything useful I'll post it. Programming a CPLD is way above my pay grade - besides, it would be nice to port the entire app over to the propeller[2?] at some point in the future. Anything I should be aware of when interfacing the PIC with the propeller?

-Dave

Oldbitcollector (Jeff)
01-20-2009, 07:12 AM
Just that the Propeller is a 3v chip. Nothing that a resistor or two can't solve.

OBC

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New to the Propeller?

Check out: Protoboard Introduction (http://jeffledger.googlepages.com/Protoboard_Introduction.pdf) , Propeller Cookbook 1.4 (http://ucontroller.com/Propeller%20Protoboard%20Designs%20for%20the%20Beg inner.pdf) & Software Index (http://forums.parallax.com/showthread.php?p=770318)
Updates to the Cookbook are now posted to: Propeller.warrantyvoid.us (http://propeller.warrantyvoid.us)
Got an SD card connected? - PropDOS (http://www.orrtech.net/propdos/)

Phil Pilgrim (PhiPi)
01-20-2009, 07:18 AM
If you can run the PIC at 3.3V, that would help to simplify the interface to the Propeller.

BTW, I think you'll be happy with the current consumption of the Propeller and its ease of programming, compared to a CPLD. (I'd hate to have to configure an NTSC driver with programmable logic.)

-Phil

Cluso99
01-20-2009, 09:21 AM
The Prop is the way to go. If you later decide to use VGA instead, you basically only have to change the object from TV to VGA. As OBC said above, he has basically done all of this already http://forums.parallax.com/images/smilies/smile.gif

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Prop Tools under Development or Completed (Index)
http://forums.parallax.com/showthread.php?p=753439

My cruising website http://www.bluemagic.biz

parts-man73
01-20-2009, 10:42 AM
Why not ditch the PIC altogether and fit it all inside the Propeller. After the TV object, you'll still have plenty of room left over for the code that the PIC is currently running.

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Brian

uController.com (http://uController.com) - home of SpinStudio - the modular Development system for the Propeller

PropNIC (http://uController.com) - Add ethernet ability to your Propeller! PropJoy (http://uController.com) - Plug in a joystick and play some games!

SD card Adapter (http://uController.com) - mass storage for the masses Audio/Video adapter (http://uController.com) add composite video and sound to your Proto Board