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Hi Ben, I just downloaded your demo of dsPIC, it only has 1 PIC listed in the devices. Is this just because its a demo?? I was just going to see what differences there were to these port registers, is it just like changing "porta" to "PORTA" etc Also from your last post, what do you mena by typecast...

Hi guys Ok. Just thought I would update on progress. I have the SD card working in PLL but not at full speed. Thanlks Ben for the pointer. Although its working its still painfully slow at loading my images. The screen currently loads 6 images measiring 90x90 pixels and it takes about 2 seconds I am ...

Hi jonny, Your on late, didnt expect a reply yet. It appears my EEPROM isnt big enough, only 125kb so thats not good since i require 3 images to be loaded at various points in the program. I just wanted to see if you could answer something for me, before trying anything else. Using the FAT component...

Hi, With Mikat's help i we have come to the conclusion that the FAT macros are slowing the screen write down too much, fastest i can get is 8 seconds, i tried low resolution but it really does look awful. I was thinking that maybe a EEPROM might be faster, although it still uses the SPI. I would lik...

Mika. When updating the LCD it starts with the pixel in the lower left corner and scans horizontally moving up a line at a time. For some reason bitmaps are stored upside down

Just out of interest. Would a PIC24 run this any faster? If it would I would consider buying flowcode fo pic24. If I could use pic24 would I need any modifications to this code?

Ok cool ill see how fast it is with this mod and get back to you

That's great. Thanks. Just one thing. Do is till save the image in 16 bit. Or 256 colour?

Also 256 colour would be ok too

Hi jonny

I might be able to sacrifice resolution for speed. Hopefully it won't look too bad.

I don't suppose I could be cheeky and ask for a guide on how to make this extra macro?

Hi jonny, I removed the load pixel macro from the loop and set it away, it fills the screen with pixels in about 1 second. So i think that rules out the LCD writes being a problem. I moved the force load to where you said and the screen definatly loads much faster :) about 8-10 seconds. I still dont...

Ok, just a bit of an update. I have got the .bmp displaying on the screen properly, had to save it in 16 bit, which isnt all that easy because not many programs support it. Altered the colours to RGB565 so thats all good now. Only thing is now i cant figure out how to make it update the screen faste...

ok, it looks like i might be almost there. I have got it to display the picture on the LCD :) There is a couple of small problems, 1: the picture is being printed 4 times across the bottom 1/4 of the screen, after about a 1/4 of the way up it turns to jargon, just random coloured pixels. 2: the colo...

Ok, i made the changes you suggested and now it initialises and then tries to open the file, when trying to open the file i get a retval "11"

I cant get it to go past this part.

Hi Jonny, i tried to follow your flowcharts, but i think im getting a bit stuck with the load_pixel macro, i think i might have messed it up, what i did was changed the fat_file_offset variable to pixel variable in a new macro, so i have 3 macros in total. Load Bitmap Load Word Load Pixel i have att...

Hi ben.

I am currently running it at 16Mhz in PLL mode. Giving me a speed of 64Mhz. I am also using the fat component.

Hi. So iv been trying different things and still can't get rid of this crappy sound. I had a chat with a few friends and they say it might be better to read the audio directly from an array at the cost of program memory. Since I have loads of memory I think this is a better option. However since the...

Hi Ben, Ok, so i played with the buffers a bit, when altering one buffer i balanced the other out to always give 512. So heres what happened, when reducing the bytes in the buffer below around 100 bytes i heard a prominent clicking, this is as described in your article, if i increase the bytes in th...

What do you mean by changing the normal buffer toi match? I thought there was just one buffer which is the part that loops 112 times. Am I missing something ?

When you say change the number of bytes do you mean the number of times it loops?

Hi Ben Thanks for your reply. I read that part of the article, I know its the buffer that stops the noise. Problem is there's not really much in the buffer part of the code to change. Its just a loop really. One thing I did notice that I jusyt wanted to check was whencompiling I get an error saying ...

Ok, no problem, thank you for looking anyhow.

Ok, so i have increased the speed upto 64Mhz incase it was a speed issue. Some of the static noise has gone, but there is a prominent clicking noise while streaming. The clicking sounds like static, think of an old LP playing, its thats sort of noise but it has a sort of frequency. By that i mean li...

Hi spanish dude,

Its the one found here:

http://www.matrixmultimedia.com/mmforum ... ming#p9320

A little bit of progress made, because i have dropped the frequency to 19.6608Mhz, it resulted in the PWM frequency dropping into the audiable range. I have altered the PWM slightly to put it outside audio range. That takes care of the high pitch squealing. I have still not been able to get rid of t...