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46  Using Arduino / Project Guidance / Re: Expand flash memory on Arduino on: September 27, 2012, 01:14:49 pm
Sorry about the mistake. That's what I thought, we might still be too slow.

We need the Arduino to measure various sensor values and sent to display.

Cannot be Android tablet as we may wanna output to different size LCDs from 7" to lets say 10".

Pi or similar would be good, but has to have a solid operating system so not to crash all the time. Also if this path is going to be taken, we need it to start up pretty fast (reason why we went with a micro-controller to start with). In addition, we don't want the users to see any start up text or GUI or anything. You turn the device on and bang it starts. Start up time can be 5-7 seconds though.

What you reckon?
47  Using Arduino / Project Guidance / Re: Expand flash memory on Arduino on: September 27, 2012, 12:45:53 pm
Library doesn't work with 115200 bps for some reason.
48  Using Arduino / Project Guidance / Re: Expand flash memory on Arduino on: September 27, 2012, 11:20:49 am
Yes I'm dumping graphics from the uSD.

When I wanna show an image and I call it, it gets drawn fro the top to the bottom and takes probably ~1 second for it to draw, need a faster time than that.



You have 300,000 pixels and write at 3840 bytes per second. I'm surprised you get it done in 1 seconds. I was expecting 10 seconds. You must be writing jpeg at large loss rate, but still the display itself is too slow than anything raw at more than 1 frame a second due to its serial connection. You want something fast, you need 8-16 or 32 bit wide bus at high speed.

Do you think it's the Arduino that's slow and not the actual 4DS module? Not that the images are stored on the uSD car on the module.
49  Using Arduino / Project Guidance / Re: Expand flash memory on Arduino on: September 27, 2012, 10:31:29 am
Pi was an example. Any low cost PC like would also be good.

I am a programmer so I Can sort out the programming on the pi/PC side with Java.

Arduino has button and some sensors. So it's needed.

Thanks.
50  Using Arduino / Project Guidance / Re: Expand flash memory on Arduino on: September 27, 2012, 09:34:48 am
Imagine it was 4DS that was slow. Is it advisable to go with a system by connecting Arduino to a Raspberry pie like platform? Have Arduino handle the control sides of things and send data to the pie to show as graphics? Is it even possible?

Thanks.
51  Using Arduino / Project Guidance / Re: Expand flash memory on Arduino on: September 27, 2012, 08:46:33 am
Yes I'm dumping graphics from the uSD.

When I wanna show an image and I call it, it gets drawn fro the top to the bottom and takes probably ~1 second for it to draw, need a faster time than that.

52  Using Arduino / Project Guidance / Re: Expand flash memory on Arduino on: September 27, 2012, 08:37:54 am
Quote
This meant each image took 15 lines of code. So imagine if I had 100 images that'd be 1500 lines of code!
I don't understand this but if you've fixed it then good.

As for the speed, do you know where the bottleneck is, you could add an ARM50 and find that it's the serial connection or even the 4DS processor.

Have you done the maths, now many bytes have to be transferred to redraw a screen? What baud rate are you using?

_____
Rob

Not sure how many bytes. The screen is 640 x 480 pixels. I am on 38400 bps baudrate. I have contacted the person who wrote the library also to see if he has tested with ChipKit or not and what the results are.

Thanks.
53  Using Arduino / Project Guidance / Re: Expand flash memory on Arduino on: September 27, 2012, 05:05:30 am
Thanks guys for all the good replies and comments.

I was busy trying to work out a way around making my code smaller, and I think I have succeeded.

The project uses a 4dsystems vga-II module connected to an LCD. I've got a uSD card in the module. Depending on some input to the Arduino images change.  I was originally calling each photo directly using the Raw technique within the 4dsystems. This meant each image took 15 lines of code. So imagine if I had 100 images that'd be 1500 lines of code!

Now I have manipulated the code, and used one of the available libraries for these modules, so each image now would have the 1 line to be shown, rather 15.

By the way the project is a prototype for a learning device for a company we're working with and may go into production, upon approval.

The next issue I have is that each image gets drawn very slowly. Do you think I need to upgrade to something like the ChipKit MAX32. I want the images to bang appear not get drawn slowly.

Thanks guys.
54  Using Arduino / Project Guidance / Re: Expand flash memory on Arduino on: September 25, 2012, 03:19:24 pm
Yes,

Need it all.

55  Using Arduino / Project Guidance / Expand flash memory on Arduino on: September 25, 2012, 12:54:51 pm
Hi everyone.

I'm doing a project using an, Arduino Mega 2560, and currently have ran out of flash memory. In other words my sketch is more than 243025 bytes of course.

Is there a way of expanding the memory on an Arduino at all? I'm stuck at the moment of what I should do.

Any help/suggestions is appreciated.

Thanks.
56  Using Arduino / General Electronics / Re: LM2917 Frequency to Voltage Converter on: August 26, 2012, 02:52:11 pm
No,

These have all been brand new with the above disconnected.
57  Using Arduino / General Electronics / Re: LM2917 Frequency to Voltage Converter on: August 26, 2012, 02:28:38 pm
The diode, cap and resistor aside and completely disconnected from the circuit and the pin 1 of the chip, the circuit pulls that much current.

I've tested this with a few of these chips that I've got. All the same.
58  Using Arduino / General Electronics / Re: LM2917 Frequency to Voltage Converter on: August 24, 2012, 05:26:52 am
Thanks again for the replies.

I connected an oscilloscope to the RPM pulse wire, with the DC offset circuit (resistor, capacitor & diode) also connected and did some test with the pulse going through the DC offset circuit and the frequencies seems to be fine.

Another thing I've found is that the reason why at higher RPMs it lows lower, is that, since the chip was getting hot the accuracy was dropping, so it seemed it was reading incorrectly. So if I leave the circuit off before it's hot, and then inject 100Hz (3000RPM) to it using an Arduino, it will read the way it should. Then of course drops when the chip gets hot smiley-cry
59  Using Arduino / General Electronics / Re: LM2917 Frequency to Voltage Converter on: August 23, 2012, 04:11:24 pm
Nope I don't have pins 4 & 7 connected to pin 6. Only pin 4 & 7 are connected and 5 & 6 connected together.
60  Using Arduino / General Electronics / Re: LM2917 Frequency to Voltage Converter on: August 23, 2012, 03:31:41 pm
I've checked the current that the circuit takes and it's about 65mA. It's supposed to take less than 5mA. This is with the input signal frequency and the output voltage disconnected.

Anyone?
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