Hello, This is an undergrad student having a little experience with 8051 microcontrollers. This year, I chose to learn about ARM Microcontrollers, so I chose a project Digital Photo Frame on VGA with ARM LPC1768. About the project, it should copy image from SD Card to some temporary storage(or this might be unnecessary, as I dont know because I have a little experience with the timings and all) and then decode it to send to VGA to be displayed on a monitor or VGA LCD. These days I have been searching for JPEG decoding steps, but they are going way above my head. Interfacing SDCard wouldnt be a problem, I guess. I have read a couple of tutorials for interfacing SD card in SPI mode, what I am concerned mostly about is how am I going to decode the image and the second problem, how to send it to VGA? Well, I am studying about VGA too these days. What I want from you guys is, where should I start with...and WHAT SHOULD I DO? Is this a doable? my email address is taha_rehman@writeme.com KINDLY HELP ME IN THIS. I HAVE TO GET GOOD GRADES. --------------------------------------- Posted through http://www.EmbeddedRelated.com
ARM LPC1768 Cortex M3 Project
Started by ●February 16, 2011
Reply by ●February 16, 20112011-02-16
"taharehman" wrote:> ...how am I going to decode the [JPEG] image ...See http://www.ijg.org/ -- Roberto Waltman [ Please reply to the group. Return address is invalid ]
Reply by ●February 16, 20112011-02-16
Roberto Waltman wrote:> "taharehman" wrote: > >> ...how am I going to decode the [JPEG] image ... > > See http://www.ijg.org/ > > -- > Roberto Waltman > > [ Please reply to the group. > Return address is invalid ]When the problem seems too complex, break it into simpler problems. E.g. leave the jpeg decoding until later in the project: start with a simple BMP image (no compression). After you are able to put a BMP on the LCD, turn your attention to jpeg. http://www.fileformat.info/format/bmp/egff.htm Bob
Reply by ●February 16, 20112011-02-16
In article <wO6dnYLADJi3usHQnZ2dnUVZ_oudnZ2d@giganews.com>, taha_rehman@n_o_s_p_a_m.writeme.com says...> > Hello, > This is an undergrad student having a little experience with 8051 > microcontrollers. This year, I chose to learn about ARM Microcontrollers, > so I chose a project Digital Photo Frame on VGA with ARM LPC1768. About theSo what are you going to use the PWM, ADC, DAC, CAN, Ethernet, SPI, I2S, I2C, QEI, UARTS etc for in this application. a lot of redundant hardware you won't be using.> project, it should copy image from SD Card to some temporary storage(orFirst simple problem work out how you are going to read the SD card and handle file systems.> this might be unnecessary, as I dont know because I have a little > experience with the timings and all) and then decode it to send to VGA to > be displayed on a monitor or VGA LCD.Second simple problem work out how you going to "send to VGA", in other words work out your graphics controller. There is no VGA on your micro you need to make one. This is simple to make but is EXTRA CIRCUITRY and MEMORY with some form of logic/PLD/FPGA to control it and deal with the memory accesses. Start with sending test patterns to you "VGA", so you can prove you can display a known image pattern. Then work out how to read bitmaps from SD card to "VGA". To test all your data paths and timings.> These days I have been searching for > JPEG decoding steps, but they are going way above my head. Interfacing > SDCard wouldnt be a problem, I guess. I have read a couple of tutorials for > interfacing SD card in SPI mode, what I am concerned mostly about is how am > I going to decode the image and the second problem, how to send it to VGA?Start simple and build up. JPEG and image scaling is about the last but one stage. Unless you also make it a criteria that images are scaled before being svaed on SD card. Last being double check ALL documentation.> Well, I am studying about VGA too these days.Sorry you are studying how certain standards for monitors work and possibly how the lowest subset of a Windows PC graphics card/ chipset works.> What I want from you guys is, where should I start with...and WHAT SHOULD I > DO? Is this a doable?This problem has been solved many times by the plethora of units on the market.> my email address is > taha_rehman@writeme.comPost on newsgroups read replies on newsgroups.> KINDLY HELP ME IN THIS. I HAVE TO GET GOOD GRADES. > > > > --------------------------------------- > Posted through http://www.EmbeddedRelated.comWhy am I not surprised. -- Paul Carpenter | paul@pcserviceselectronics.co.uk <http://www.pcserviceselectronics.co.uk/> PC Services <http://www.pcserviceselectronics.co.uk/fonts/> Timing Diagram Font <http://www.gnuh8.org.uk/> GNU H8 - compiler & Renesas H8/H8S/H8 Tiny <http://www.badweb.org.uk/> For those web sites you hate
Reply by ●February 16, 20112011-02-16
"taharehman" <taha_rehman@n_o_s_p_a_m.writeme.com> wrote in message news:wO6dnYLADJi3usHQnZ2dnUVZ_oudnZ2d@giganews.com...> > What I want from you guys is, where should I start with...and WHAT SHOULD > I > DO? Is this a doable?ARM's 'mbed' prototyping system uses the LPC1768. There's a discussion on VGA interfaces here: http://mbed.org/forum/mbed/topic/186/ The Cookbook has some SD Card-related articles: http://mbed.org/cookbook/Homepage Regards, Chris Burrows -- CFB Software Astrobe v3.2: ARM Oberon-07 Development System http://www.astrobe.com
