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1  Using Arduino / Storage / Re: loading images from external memory on: August 21, 2014, 10:01:46 am
I would not bother with any other type of external memory until I am sure I tried everything with the SD card.
Try using the real sdfatlib instead of SD.h. Also do not read byte by byte if you are doing such. Try reading 512 bytes and then send those 512 bytes to the lcd screen and repeat until done. Also make your own image format for example
uint16_t width
uint16_t height
(Data that is already in LCD's native pixel format and does NOT need any conversion).
Doing this should cause a speedup. Also another idea is instead of just storing the already converted data to whatever the LCD screen uses, if your images does not have that many colors you can first store a palette (a table of colors that are already in the LCD's native format) and then just store what entry should be used in the palette. Doing this can double the reading speed if not more.
2  Using Arduino / Sensors / Re: ov7670 with both arduino uno and now mega on: August 21, 2014, 09:48:33 am
Glad I could help. Actually when using the stm32 I made a slightly different protocol. After sending RDY I sent the line number that was about to be sent. This allowed for quicker synchronization. Yes I also get the same issue.
3  Using Arduino / Sensors / Re: ov7670 with both arduino uno and now mega on: August 20, 2014, 07:54:33 pm
Yes it could, I added a windows binary https://github.com/ComputerNerd/RawCamera-data-converter/blob/master/convert.exe.7z
What I did instead of bothering to compile libpng and zlib I just used a different library called miniz. It has support for saving a png file so I used it. The reason for doing this is to keep executable size down and also I found that it saved the png file faster and had a similar filesize.
4  Using Arduino / Storage / Re: Find and delet word??? on: July 25, 2014, 03:37:56 pm
This is just sheer laziness. He did not even bother to correct the title by editing his post. Also not even one proper sentence. I bet he just had a question that popped into his head and quickly asked it without given a second of though himself. Sorry I am not helping you figure this out on your own or come back when you have tried something and if that fails ask a question.
5  Using Arduino / Sensors / Re: Cannot access i2c/twi on ov7670 cmos sensor on: July 25, 2014, 02:23:48 pm
What do you mean by "type of the camera module spec"? Have you even tried my code?
6  Using Arduino / Storage / Re: arduino and excel on: July 25, 2014, 08:59:36 am
I think he wants to go the other way meaning export data from an excel sheet to the arduino. The way to do that is to simply convert the data to an array and store it in flash memory. I noticed you mentioned waves maybe you could approximate your data with a formula? Depending on how well you can approximate or exactly calculate your data in real time this may be a better option regardless of whether you can cram in the data or not. Or you could even combine look up table with calculations.
7  Using Arduino / Sensors / Re: ov7670 with both arduino uno and now mega on: July 24, 2014, 01:45:38 pm
To answer your questions.
1. You could try a voltage resistor divider. I have not tested it myself but it won't hurt to try. Also you need pulls ups for i2c. The resistor value does matter. I have found 10k to work just fine, I also remember testing 4.7k and that worked fine too. However using a resistor that has too much or too little does not work for example when I tried a 1k it would not work. The two resistors will be a pull  up resistor to 3.3v. The way this works is you plug in the i2c pins to 3.3v using the resistor and then plug that into the ov7670 all wired up together. Another thing is to disable the internal pull up resistors, they are off by default however the arduino wiring library enables them please follow my instructions on how to disable the internal pull up resistors if using the wiring library.
2. When I first got the ov7670 I also made that mistake and it works just fine. I do not think this will cause any damage I am more concerned about the internal pullup resistors causing damage however when I first got the module (if I remember right) I did not disable the internal pull resistors and the ov7670 still works but when enabled I do not remember having any luck with writing and reading resistors. However just because I got lucky does not mean you will.
3. Why are you bitbanging? Use the hardware i2c peripheral. Try my code, it uses hardware i2c and it works fine for me. Also the ov7670's i2c address is 0x42 the LSB (bit 0) is set to 0 when writing and 1 when reading so yes you do use 0x43 to read. Also when using the wiring library you must specify the 7bit address so use 0x21.
8  Topics / Device Hacking / Re: Interfacing 8MP Apple/Samsung camera modules with arduino uno on: July 16, 2014, 11:42:22 pm
While being a nice idea you need information on the cameras before you can expect to use them. You need to know what sensor is in the module and you will need a datasheet and you will also need the pinout and a means to connect the small FPC cable to the arduino. Also if it does not use parallel output (like LVDS) you will need a chip to convert it to parallel data. Another idea is to just buy a camera module that is indented for hobbyist instead of mobile phones.
9  Using Arduino / Microcontrollers / Re: Why 16 Mhz clock??? on: July 15, 2014, 05:12:05 pm
I also ask Why 16mhz clock however the reason I ask it is because the avrs are rated to run at up to 20mhz so why not clock it at that frequency?
10  Development / Suggestions for the Arduino Project / Re: Does Arduino have a future? on: July 15, 2014, 09:52:18 am
fat16lib I must say that I have had a similar experience with the stm32f4 discovery board. Today I was messing around with some of my camera modules that I own and was amazed on the ease of use. All I had to do was setup the DCMI and DMA peripheral and then I can easily take pictures without cpu intervention. I also wrote a program that does real time sample synthesis that is impossible on the arduinos based on AVR mcus.
11  Using Arduino / Sensors / Re: Camera module for Arduino on: July 13, 2014, 09:58:30 am
I do not think you need a raspberry pi. The ov7670 can output a 40x30 image which fits in ram.
40x30x2=2400 and you have 2.5kb of ram.
http://forum.arduino.cc/index.php?topic=159557.0
Or you could use a higher resolution and just read what you want. Or you could configure the output window.
Another option is to use external spi ram or use the fifo version. However if you don't want any of that it may still be doable.

Also the sparkfun product is jpeg. How are you going to decode that in real time on the arduino for color tracking?
12  Using Arduino / Sensors / Re: ov7670 with both arduino uno and now mega on: July 13, 2014, 12:12:34 am
No. I just looked it up and I have not used it. The arduino is not true usb, it just uses microcontroller programmed to do serial<->usb.
13  Using Arduino / Audio / Re: Pulsing a sound sample from Attiny85 on: July 12, 2014, 11:19:39 pm
You need to completely remove
isPlay=0; the whole line
Also remove
isPlay=1;
from the loop
Also write your own code to check if the button is pressed it is not that hard but I want you to do it. I am sure you are capable of figuring it out. I have already done more that I should have for code that you should be writing.
14  Using Arduino / Sensors / Re: ov7670 with both arduino uno and now mega on: July 12, 2014, 10:13:06 pm
Alright good to hear that my new program seems more viable for people.
15  Using Arduino / Sensors / Re: Is it Doable to use IMAGE PROCESSING for waste segregation?. on: July 12, 2014, 11:36:08 am
You know saying it is 100% impossible may not be correct but very challenging. It might be possible to at-least do the project in part. I would not want this project as a requirement to graduate. I think there may be ways to differentiate between say paper and cans as they have a different shape. I want to know more about the recycling facility. Is just a conveyer belt with items neatly placed on there or is a huge mess of fast moving objects? The latter being impossible if one item hides another. I have not tried doing this so I should not judge impossible or not. Why not asking the person who gave you the assignment what experience they have. For example have they completed their own project.
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