Cheap FTDI video driver chip breakout board

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I've heard that Gameduino (not Gamebuino) uses that chip in order to unload the AVR's CPU time from rendering the picture. I'm wondering if it's possible to get a development board with it somewhere at a cheap price because it's just a chip. I don't know why breakout boards cost so much more than one little chip. If I could get a schematica of that chip and an XMEGA and know how to solder TQFP100, I'd do it myself.

 

Sidenote:

I'm very disappointed with the poor speed of XMEGA's MSPI which I expected to be 64MHz (darn mystifications!) so I cannot really put enough fast speed to a serial display, hence I quit the driver porting project after reading the datasheet to set the baudrate. According to my calculations, with such low speed, it's impossible to render the picture enough fast for a 16-bit 128x160 screen.

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I think the chip you are referring to is FT800 http://www.ftdichip.com/Products/ICs/FT800.html

 

The reason dev boards cost what they do is because that how much it costs to make them :). The real question is "why are mass produced boards so cheap?" The answer is that methods for mass production have a high setup cost, but a low per unit cost. A similar thing is true for purchasing, buying a million units of a component is cheaper per unit than buying 10 units, because the vendor has a fixed cost per sale.

 

So on big production runs, the fixed cost is spread over many units, and the more you make the cheaper it gets. But on small runs, the fixed cost works against you, as it is spread over fewer boards.

 

"Cheap price" is a relative term, but if you are looking for something like $10, probably the only way is to make your own. Soldering TQFP100 is not the easiest way to learn, but it could be done.

Bob.

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If that's the chip then FTDI sell a whole range of boards themselves.

'This forum helps those who help themselves.'

 

pragmatic  adjective dealing with things sensibly and realistically in a way that is based on practical rather than theoretical consideration.

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Foxcat385 wrote:

... it's impossible to render the picture enough fast for a 16-bit 128x160 screen.

 

What speed do you need - it seems 128x160 is not that many pixels, and even 16M SPI gives 48.8 fps ?

What speed can the LCD accept ?

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The ST7735 can have only 15MHz speed which means I cannot use 16MHz, but 8MHz. The calculations were disappointing. I don't know how to set the framerate of the display. I'd like to set it to 10FPS, but I seriously don't understand the datasheet parameters. There's a clock parameter, but I don't know the clock's value. Kinda like a physics test where I miss a variable or a formula and get an F. And since the display has only SCK and SDA, it's hard to turn the SDA pin on XMEGA into an input pin very fast. I mean, it's impossible! Both MISO and MOSI are the same pin! I looked up the datasheet. So thereby, I cannot get the VSYNC to synchronize to avoid tearing.

 

In my wishes, 60FPS would be the best or 50FPS at least. The console project needs to have a bigger resolution from at least a GameBoy Color. In the best situation, it should have bigger resolution than NES (256x240). This means either 220x178 or 320x240. So I thought if the FTDI driver could drive the display to not overload the poor XMEGA with video processing.