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Yes, that’s the Seeeduino Mega. I don’t buy off of eBay, though, because the boards are often counterfeit. You can buy directly from Seeed Studio:
http://www.seeedstudio.com/depot/Seeeduino-Mega-p-717.htmlThe shipping is pretty fast.
No, external interrupts are not enough. One of the microcontroller’s input capture pins needs to be connected. That’s not the same as an external interrupt. From my article about the problems with the Arduino Mega:
To perform video overlay, the Video Experimenter relies on an input capture pin (to capture the exact time that the pin has changed state). Even though the ATmega1280/ATmega2560 has 4 input capture pins, none of them are connected!
The Due will absolutely not work because it has 3.3V operating voltage.
The Uno R3 SMD edition is functionally the same as any other Uno.
The Video Experimenter will not work on an Arduino Mega. The analog comparator pin on the microcontroller chip is not even connected to the board. I tried to make that clear here: http://nootropicdesign.com/ve/whynotmega.html
You can use a Seeeduino Mega, which will give you more memory for higher resolution.
http://nootropicdesign.com/projectlab/2011/07/13/ve-on-the-seeeduino-mega/It is not faster, though. Framerate is typically not an issue for Video Experimenter projects, as you can update the pixel frame buffer very fast.
I’m glad it’s working for you, john.k. I’m not sure what to think about the problems uploading a sketch to the board when the wiring is in place. I don’t think I ran into that problem.
1) Why do you think the VE only works with the seeduino? The product page clearly states that it is designed for Uno and Duemilanove. http://nootropicdesign.com/ve
2) Yes, it is tricky to use interrupt-driven devices in conjunction with the VE, but it may be possible depending on how you code it. You can read the serial port by using the pollserial library. There are examples of pollserial with the VE library. As for GPS, see this project:
http://nootropicdesign.com/projectlab/2011/05/20/overlay-gps-on-video/The female headers included in the kit do not have the long pins. If you have “arduino female headers” with long pins, then you can certainly solder them on the outside set of pads. This kit was designed many years ago, and female headers with long pins were not available for a decent price.
Make sure you don’t solder the female headers that don’t have long pins to the outside pads, because then there are no male pins to plug into the Arduino!
Generally, this shield is not going to be stackable with anything else because it uses a lot of pins and functions of the Arduino. What shield do you think is stackable with the Video Experimenter? Most shields are not stackable from an electrical perspective.
I don’t understand the question. The Adafruit libraries make it easy to set the pixels to whatever you like, so for your particular project it’s just a matter of coding it up. I’m not sure I understand what you mean by “cascading”.
allowing the output voltage of the pin11 to be between 0 (0 duty) to 4,92V (OCR2A = 255 = 100% duty)
You keep implying that the voltage can be between 0 and 5V. It cannot. The actual voltage on the pin at any given time can be either 0 or 5V. A PWM pin simply toggles between these 2 voltages at different rates and duty cycles, but it is NOT a DAC. The guy on the arduino.cc forum told you that a 50% duty cycles gives you 2.5V, but that’s just wrong.
I’m not saying that you can’t do some good sound, but you are limited to square waves.
Have you actually tried that on a Hackvision or Arduino though? Are you doing all that with square waves? You can only generate square waves with PWM.
So PWM on pin 3 is not working? Hmm, it should.
pollserial is used just like Serial. Only use pollserial on the Arduino with the VE. The other Arduino just uses normal Serial.
This is the example sketch that comes with TVout:
#include
#include
#include
TVout TV;
pollserial pserial;
void setup() {
TV.begin(_NTSC,192,128);
TV.select_font(font6x8);
TV.println("Serial Terminal");
TV.println("-- Version 0.1 --");
TV.set_hbi_hook(pserial.begin(57600));
}
void loop() {
if (pserial.available()) {
TV.print((char)pserial.read());
}
}You will be limited in how much data you can transfer because thei pollserial implementation is only polling for data during the horizontal blanking interval. Hope this works for you.
Basically, when you are doing video on an Arduino, you require exact timing. You can’t do serial communication at the same time. The TVout library comes with a polling version of serial (the pollserial library). Use that on the Arduino that is running the TVout code.
I am not sure why the PWM on one pin is causing different speed than the other. Perhaps you can just adjust it in software?
Bottom line is that it is difficult to do other things on an Arduino when you are generating a video signal.
I am guessing that M2 is the motor that does not work when the VE is being used?
The video library uses Timer1 to control all the timing. This means you cannot use pins 9 or 10 for PWM. You can still use pins 5,3,11 for PWM.
I would try this:
int E1 = 5; //M1 Speed Control
int E2 = 3; //M2 Speed Control
int M1 = 10; //M1 Direction Control
int M2 = 11; //M2 Direction Control
