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Camera selection help needed. — Parallax Forums

Camera selection help needed.

TagametTagamet Posts: 22
edited 2011-09-20 19:22 in Propeller 1
Hello all!
I am new to this forum and relatively new to Propellers. I am developing a project where I plan to transmit still color images and low quality B&W video using XBee modules. I've come across so many terms (UART vs. SPI, CMOS vs TTL, PAL vs. NTSC) and code, my head is spinning. I've found a couple of demos, but would just really like to find out what the propeller can support, if I need any conversions, transmit & receiving speeds, etc.

Thanks,

Tagamet

Comments

  • Mike GreenMike Green Posts: 23,101
    edited 2011-09-20 09:29
    Because the Propeller does almost all of its low-level I/O in software, the question of what the Propeller can support depends mostly on what software you're using. Many of the things you've mentioned are supported by software in the Propeller Object Exchange (the OBEX) that you incorporate as part of your program. The Propeller Tool comes with many of these objects from the OBEX like FullDuplexSerial and both TV and VGA I/O drivers.

    The PAL vs. NTSC is partly hardware and partly software in that the Propeller's video generator can produce either type of color TV signal and, while most TV driver software is configured for NTSC, it's straightforward to change a couple of lines in the TV driver source to have the video generator configured for PAL.

    The CMOS vs. TTL issue is less about CMOS and TTL logic (see the Wikipedia for descriptions of both) and more about voltage levels. The Propeller is built for use with 3.3V logic levels (3.3V = 1, 0V = 0) while older devices are built for use with 5V logic levels (5V = 1, 0V = 0). 5V applied to a Propeller input can damage the Propeller. There are lots of fixes for this. The simplest is to put a 2.2K resistor in series between the Propeller I/O pin and the 5V device's output pin. There's a whole long thread on various solutions to this interface issue. Look for "How to safely interface a 5V signal to the Propeller" here.

    Spend some time looking through the information in the above Key-Thread-Index and looking over the Propeller Education Kit tutorials. You might also browse the Propeller Object Exchange for existing I/O routines.
  • TagametTagamet Posts: 22
    edited 2011-09-20 11:28
    Mr. Green,

    Thank you for all the info! I have the Propeller Education Kit & various sensors now and will order the Xbee Starter Kit, Spinneret, and a VGAPS/2 Adapter Board Kit later this week. I've found all sorts of cameras from ranging in price from $20 to $100 from various websites. Cost isn't nearly as much of a factor as success is with a reasonable amount of programming & minimal other hardware requirements. I will definitely go through the OBEX again soon.

    Thanks again,

    Tagamet
  • TubularTubular Posts: 4,726
    edited 2011-09-20 19:22
    Hi Tagamet, and welcome to the Parallax forums.

    I'd recommend the 4D systems uCam-TTL, which I've used in commercial products, because they come with software to get you up and running / preview with a PC straight away.

    There are some options covered in this thread

    cheers
    tubular
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