USB interface

Fuck off, RichTard.

Reply to
Mr.Eko
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Different part, ultra low power version. I have been looking at a solution that uses much less memory 256 k by 8 so the required memory is only about $2.50.

Bob

Bob

Reply to
<castlebravo242

this:

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not spendy, easy to use, and

Solar charged NiCad, replaceable, of course.

Reply to
Archimedes' Lever

the

this:

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not spendy, easy to use, and

Solar cell would need to be 3 to 4 times the PCB size, and they are not cheap. We can cut down power on the uC, but not much for the sensor.

Reply to
linnix

the

this:

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not spendy, easy to use, and

Typical calculator cell is 1 cm by about 3.5 or 4 cm. I am fairly certain that they can drive a few mA.

They can certainly drive a trickle charge circuit that provides the cell(s) with the higher voltage they need to accumulate a charge.

Also, the crank drive units all over the market are pretty nice. Hell a super cap could probably do it.

I guess it all comes down to how long the operation cycle is expected to be.

Reply to
Archimedes' Lever

wrote in news:68Owl.15020$ snipped-for-privacy@flpi146.ffdc.sbc.com:

The clarity and amount of information contained in a single word response stands in contrast to the SNR common in newsgroups.

Reply to
Robert

By altering the way in which data is stored, using a counter rather than a memory location to indicate time, I can reduce my memory requirements from 2 Mbyte to 128 Kbytes. I only store when there is data to be stored, not on every clock cycle. I need to do my homework to figure out the usb protocol end of the deal.

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snipped-for-privacy@att.net/walking.pdf

Bob

Reply to
<castlebravo242

Hi Bob,

I have followed this thread from the beginning.

I think you have not thought this all the way through.

Your RAM interface may give you an easy front end, but does nothing for the USB backend.

One of your posts mentioned an heart rate monitor and a few switches.

That kind of data is not that fast.

Most higher level processors can do that.

I would guess that you are not a embedded programmer.

I see this entire project can be done with a processor and some A/D converters.

Once that processor is selected and the interfaces are designed, the rest is software.

Good luck on getting this done.

don

PS: Let us know when you get something working. It will be interesting what direction you go.

Reply to
don

Your remark, however, does not.

Reply to
Archimedes' Lever

A/D converters? I do not need to measure analog levels, only edge transitions. I am interested in time measurements. The time of each heartbeat, the time of each foot fall and the time of each button push. I have created some test files with software and played with processing it. I intend to do like wise with the new proposed format.

Bob

Reply to
<castlebravo242

So, just like our project, It doesn't make sense to have USB build- in. We have an external USB to SPI converter to map the uC EEPROM to a mass storage device. It can also share a micro-SD card between the uC and PC.

If you don't need A2D, your entire project can be done with a 50 cents uC and a micro-SD card.

Reply to
linnix

I basically need an accurate 1 khz clock, a 24 bit timer, an 8 bit input register that detects transitions and something to store the timer and input register data if there has been a transition. Then I need to input the data to a computer to process it. The signal conditioning logic at the input port will vary with the specific input devices.

Bob

Reply to
<castlebravo242

Any 50 cents uC can do that.

With a uSD reader.

Reply to
linnix

Try using Alt-230 to get µ instead of u

Reply to
Capt. Cave Man

OK, until I forget it again. =B5C w/ =B5SD.

Reply to
linnix

That's what I get from my database front end programming days before GUIs were around yet. Border codes and the like. The extended character set. I remember too many of them, actually.

Einstein said that we should not commit to memory anything that we can look up as it 'clutters the mind'.

I have such a huge basket of cluttering in there, I don't think this one (extended codes)is all that significant. It actually helps at times.

It makes me smile when the dope that claims I am afraid of math chimes in.

Reply to
Capt. Cave Man

With the amount of existing stuff, i would seriously consider going with a bluetooth interface.

Reply to
JosephKK

I am kind of liking the idea of writing directly to an sd card.

Bob

Reply to
<castlebravo242

And that is only a tiny fraction of the current needed for the rest of the device. You will be pissing away several mA (or more) while collecting data. Might as well use flash, 0 current to retain data.

Reply to
JosephKK

seems to be incurable also.

Reply to
richard

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