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31  Products / Arduino Due / Re: USB mouse basic question on: January 27, 2013, 03:53:11 pm
thanks, i'll try to change that value. 1 ms polling will be MUCH better. it might even make the following question redundant but here it is anyway:

i want to have a servomotor directly follow mouse motion. my program currently does this beautifully while also writing the motion timing values to SD card (thanks to the SDfat library which works sooooo well on the DUE) i use a quadature encoder for the HID and a decoder chip to run the servomotor driver (Gecko, which is one great brush motor driver) this all works very well but i want to use a cheap optical mouse instead of having to build the HID myself. soooo, i really want the mouse to report every tick it moves instead of how far it moved in the polling period. if the polling period is 1 ms, this might just solve the problem because the motion will probably be either 0 or 1 and never more if my main loop is tight enough.

does this sound possible?
32  Products / Arduino Due / Re: Due EEPROM alternative? SD? on: January 26, 2013, 02:51:34 pm
i am very interested in this. how complete is the library? can i start fiddling with it as it is or is there anything to look out for? i tried unsuccessfully to get similar chips to work with the digilent chipkit board which is one of the reasons i switched over to the DUE. it took me just a day to rewrite a major sketch to work on the DUE and it is perfect with the SDfat library that was not available for the chipkit.

i bought some Micron 5PQs because they are 128 meg and looked very useful. the instruction set is similar to the one you are using. i was never able to get it to work reliably. do you have any interest in checking the data sheet, comparing to the EEPROM you are using and possibly add it to the library? i would love to have 128 (8 by 16 meg) meg available for high speed data aq. dual or quad read/write modes would be great but not essential.
33  Products / Arduino Due / Re: Due EEPROM alternative? SD? on: January 26, 2013, 01:45:31 pm
i am writing and reading 512 byte buffer dumps to an SD card in 1.1 ms while running an external interrupt and doing a fair amount of processing. SDfat works about two to four times faster than the original SD library and also has a bunch of fun methods.
34  Products / Arduino Due / Re: Connect a USB hub? on: January 26, 2013, 01:39:37 pm
i had no problem with the mouse example and a perixx wireless mouse. i was actually surprised that it worked. i guess this mouse is more generic than others. $12 from Amazon and a great mouse for the price http://www.amazon.com/gp/product/B0067A846Y/ref=oh_details_o01_s00_i00
35  Products / Arduino Due / newby pleased so far on: January 25, 2013, 02:00:18 pm
i just got my DUE a couple of days ago. i have been screwing around with the Digilent Chipkit for about 6 months because i needed something fast. the Chipkit uses a good processor but there are all sorts of problems with libraries and there does not seem to be a large enough user base that anyone fixes the problem, other than maybe for their own use and not for sharing. to me it is pretty amazing that basic libraries such as SD, are full of bugs and no one seems to care enough to fix them. i thought that Arduino was for people (like myself) who just want to get things working and not spend a lifetime looking at datasheets and debugging other people's code.

i was thrilled when i saw that the DUE was available. it has the speed of the Chipkit and many more features which i hope to exploit. i was concerned that i would have the same "new item" problems i had with the Chipkit. SO FAR I HAVE NOT AND AM EXTREMELY IMPRESSED. i do understand that i will find problems with a new product but have much greater confidence that the problems will be fixed. i waited for 4 months to see a working SD library for the Chipkit and it never happened. SDfat seems to work well on the DUE, writing blocks in half the time and working with a variety of cards. i could find only one card that worked well with the SD library for the Chipkit.
36  Products / Arduino Due / USB mouse basic question on: January 22, 2013, 03:37:11 pm
i am awaiting the delivery of my Due and trying to figure out as much as i can before getting it. i read the example mouse controller sketch and am trying to determine if it will work for my application. i am currently using a quadrature encoder connected to a chip that converts the quad to step and direction. the step pulse is connected to an interrupt pin so every time there is a pulse, the interrupt code is run.

it is my hope that the USB mouse controller can be used in a similar way, that i can detect any mouse motion and use this to send step pulses.  exactly how does the usb task interact with the main loop? how often is the (mouse.getXChange() updated? is there a document that explains this? i have not found one yet.

37  Using Arduino / Audio / Re: Wavetable pulse generator? on: November 02, 2011, 12:49:13 am
I need to produce signals to be recorded on a computer sound card input. The goal is to record WAV files that are 0 centered (127 or whatever as center of an AC signal). It seems that the sound cards are very cooperative as they have a rest voltage of 2.5 volts so providing a signal that goes from 0 to 5 volts produces exactly the recording that I want. I am currently using a triangle wave generator made of op amps and comparators but want to do it with the Arduino instead so the timing of the pulses can be based on a clock instead of RC networks. I am driving the circuit with a short squarewave pulse that comes from an encoder. I need to produce a single pulse that goes from 0 to plus peak, to 0, to negative peak and back to 0 each time the encoder pulses. I actually need to produce pulses of two different wavelengths depending on the direction the encoder is turning. I am using an integrated circuit that converts the encoder quadrature signals into step and direction signals. Eventually I also want to do this with the Arduino but will tackle the quadrature decoding at a later time if I can get the pulse generation working first.
38  Using Arduino / Audio / Wavetable pulse generator? on: November 02, 2011, 12:09:02 am
I am new to Arduino and do not have much experience with C. I am trying to generate triangle or sine pulses within a sketch. I need to produce a pulse of one full wavelength triggered by a digital input pin read in a loop or by generating an interrupt from a signal change on a pin. I have found some useful code to produce the sine or triangle waves with wavetables and PWM but can not figure out how to generate a single pulse at a precise time within a loop that is polling the input pin or when an interrupt is generated. I am sure I could find the answer if I look long enough but I have a satellite internet connection and it is unbelievably slow. I am hoping that someone can point me closer to the solution than I can get by hours and hours of searching.  I have a sketch by Adrian Freed that I can get to produce tones but can not figure out how to get it to produce single wavelength pulses. here is the link to the sketch. Maybe someone can suggest how to get this to produce the pulses that I need in response to an input pin. http://adrianfreed.com/content/arduino-sketch-high-frequency-precision-sine-wave-tone-sound-synthesis
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