XMega SRAM slow turnaround? - Solved (Glitchy Power Supply).

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Yeah, your vector demo was cool!

I already have a driver for both the Atari and SNES joysticks built into my video engine, but for simplicity's sake, I will choose one or the other.

As for the video timings, I run the 640x480 VGA standard remapped to 64MHz like so...

///////////////////////////////////////////////////////////////////////
////////// AVRCADE.COM - 200 X 150 VGA AND STEREO SOUND ENGINE
////////// ROUTINE BY RADBRAD - AUG-10-2012
///////////////////////////////////////////////////////////////////////
#include 

// 640 X 480 @ 64 MHZ HORIZONTAL PIXEL TIMING
// HSP : 0244 FROM 0000 TO 0243
// HBP : 0122 FROM 0244 TO 0365
// HPX : 1627 FROM 0366 TO 1992
// HFP : 0041 FROM 1993 TO 2033
// TOT : 2034

// 640 X 480 @ 25 MHZ VERTICAL LINE TIMING
// VPX : 450 FROM 000 TO 449
// BBD : 015 FROM 450 TO 464
// VFP : 011 FROM 465 TO 475
// VSP : 002 FROM 476 TO 477
// VBP : 031 FROM 478 TO 508
// TBD : 015 FROM 509 TO 523
// TOT : 524

// SINGLE 256 COLOR
// 200X (1627/08) X 150Y (480/3) = 30000 / FREE = 02768

// DOUBLE 256 COLOR
// 125X (1627/13) X 120Y (480/4) = 30000 / FREE = 02768

When you have 64MIPs available, might as well squeeze every but of juice out!

Brad

I Like to Build Stuff : http://www.AtomicZombie.com

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Do you get strange phase issues on a normal LCD monitor with that timing? Would 62.5Mhz let you have a nice even 1600 clocks for ative-pixel-time or am I being too pedantic?

Did some spreadsheet/napkin calculations.

8K per screen and double buffering and I should be able to pull this off

http://www.youtube.com/watch?v=j...

Are you going to have an SD card so it could play the sampled sounds ?

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There is a bit of pixel phase correction on the monitor, but to keep this project simple, I opted for an easy to find 8 MHz external xtal running the PLL up to 64MHz.

My second dual SRAM + logic version will keep to the exact standard, running 25.175 MHz base X2 PLL.

Brad

I Like to Build Stuff : http://www.AtomicZombie.com

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Mr Zombie,

Are you planing on putting an SD card on one of the SPI ports?

Would be good for playing sampled sounds (as in Starwars), but also there is a crazy video mode I wanted to try on the UzeBox but it just didn't have quite enough grunt for it. I think with single cycle memory access the xmega might be able to pull it off.

Plus having an SD card would make porting my version of Tempest to your hardware much easier.

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larryvc wrote:
Brad, it's nice to see you are still around. Happy Holidays!

Hey thanks, just seen your post!

Have a great new year.

Brad

I Like to Build Stuff : http://www.AtomicZombie.com

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andrewm1973 wrote:
Mr Zombie,

Are you planing on putting an SD card on one of the SPI ports?

Would be good for playing sampled sounds (as in Starwars), but also there is a crazy video mode I wanted to try on the UzeBox but it just didn't have quite enough grunt for it. I think with single cycle memory access the xmega might be able to pull it off.

Plus having an SD card would make porting my version of Tempest to your hardware much easier.

Not for this one.

My #1 goal was to have ONLY a single XMega and no other ICs.

The fun will be making a demo or game entirely inside the XMega. I am documenting the entire audio.video driver as well so those who wish to dive into assembly can see how easy it really is. For those who just wish to explore the XMega and code in C, i have made things as easy as possible.

I was considering an SD card on the more powerful version, but to this day I have yet to see a working SD card library for any AVR, so probably not.

When I say "working", I mean not full of bizarre quirks that require jumping through hoops like a circus bear to make certain cards work or to make FAT work properly. If every something comes out that works 100%, I certainly will.

I do however, have a routine that allows the use of an external EEPROM to mirror the XMega, working like a cartridge. I may add that to the new system.

Brad

I Like to Build Stuff : http://www.AtomicZombie.com

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AtomicZombie wrote:

I was considering an SD card on the more powerful version, but to this day I have yet to see a working SD card library for any AVR, so probably not.

When I say "working", I mean not full of bizarre quirks that require jumping through hoops like a circus bear to make certain cards work or to make FAT work properly. If every something comes out that works 100%, I certainly will.

I do however, have a routine that allows the use of an external EEPROM to mirror the XMega, working like a cartridge. I may add that to the new system.

Brad

AFAIK the Uzebox has no issues with SD cards for general use.

This page

http://uzebox.org/wiki/index.php?title=SD_Card_Compatibility_List

that is talking about SD "compatability" is just about speed for use with the video demo

http://www.youtube.com/watch?v=hWWsSn_QKLM

Those cards listed above are not fast enough at sector boundaries. The demo is streaming "the matrix" video straight off the card. With some brands of SD cards there is up to a 1/10 second pause at random points along the way. The poor little AVR can not buffer and deal with that the same way a 3Ghz/16GB desktop can.

For using the bootloader/gameloader

http://uzebox.org/forums/viewtopic.php?f=3&t=520

Just about any SD card will work as it does not need the speed the video demo does.

It is mainly ELM Chan FFS stripped down a bit I think if you want to have a look at that.

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Thanks, will have a look.

Judging from the oodles of posts here trying to get the EC FSS working, I just figured it wasn't worth the hassle.

My own prom loader just kicks the entire .HEX to the Xmega and has a routine to go the other way so you can duplicate games, making it act like a cartridge system.

Brad

I Like to Build Stuff : http://www.AtomicZombie.com

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