More Memory for Camera

Robert T

I have been going through Hanno's code for reading the small camera and I am in the process of setting up the hardware to test the camera.

So what if I want to read an NTSC signal and create an 640 by 480 by 8 bit (gray scale) image in memory. Since I only have 32K of RAM to store the image, what are my options for more memory.

Would an SD card be too slow? How about the memory expansion module from machine intelligence?

Peter KG6LSE

SD is Plenty fast enough if driven with a decent device some do 15MbPS

Peter KG6LSE

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peterthethinker.com/tesla/Venom/Venom.html
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Mike Green

An SD card would be way too slow. The problem is that you have a huge amount of data (640 x 480 bytes = 300+K) and SD cards are, at their heart, flash EEPROMs which take milliseconds to write. They're buffered, but the buffers are only so large, nowhere near enough for the amount of data you're talking about.

You need to use a large parallel static RAM for a buffer and those require a large number of address bits. Look at the various threads on Z80 and other processor emulation. Several people have various designs incorporating large (512K byte) static RAMs. The Morpheus board includes VGA output drivers and it shouldn't be too hard to use some of the same ideas for buffering video input.

mikronauts.com/products/morpheus/
http://forums.parallax.com/showthread.php?p=790917
www.smarthome.viviti.com/propeller

Robert T

Thanks for the leads Mike

I wanted about 2Megs of RAM for image storage and manipulation.

Looks like my options are:

1. Morpheus board with Mem+
2. Cluso's Multiblade Prop
3. Machine Intelligence Technologies: Static RAM Memory Expansion Kit

Would love to hear from anyone about experiences with any of these.


Robert

Mike Green

I would suggest the Morpheus with Mem+. The Multiblade Prop is really designed for 512K of RAM although it can handle a single 2MB (expensive) static RAM. The Morpheus with Mem+ uses 512K static RAMs which is a much cheaper way to get 2MB.

I would stay away from the Machine Intelligence Technologies products mostly because they're not particularly open about their products. Bill Henning provides lots of information about Morpheus, both hardware and software, on his website for you to take a close look at the products without having to buy them first. You can buy bare boards if you want or you can buy kits or assembled and tested units.