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Add USB to any PIC project for less then $3

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awesome!!! Burt i will see if i can do it. I want to add some cool features to the board im sure everyone would love. I already added the alarm but need a buzzer which is what im doing now. The code is done! heh...

I also have to learn some cool effects like transitions. I will be adding a Slideshow mode since most people like that. Also allowing people to change the speed and effect to change images.

Burt i think its 10,000 units...

https://www.electro-tech-online.com...PPLICATION20FOR20SUBLICENSE20TO20USB20VID.pdf
 
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as time passes, the adopter number might remain CA42 cable, but inside device might change to PL2303 or something like that, i suspect.
 
awesome!!! Burt i will see if i can do it. I want to add some cool features to the board im sure everyone would love. I already added the alarm but need a buzzer which is what im doing now. The code is done! heh...

I also have to learn some cool effects like transitions. I will be adding a Slideshow mode since most people like that. Also allowing people to change the speed and effect to change images.

Burt i think its 10,000 units...

https://www.electro-tech-online.com...LICATION20FOR20SUBLICENSE20TO20USB20VID-1.pdf

It may be I been a while back when I look it up it could of been changed, It's like $5,000.00 to get your own
I was going to try some 18f14k50 with usb. for usb to rs232 for the pic but I think it would be a waste of time.

But I can make one with it. But how would you beat a part like mike posted for less then $3.00
 
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MCP2200 Looked at them to there nice maybe the best way to go. If you want usb to rs232 There a chip on the market

That's like 25 cents each in lots of 1000 and is plug and play with windows xp up to window 7 And it has it's own 3.3 volt on board regulator
cp2102 there $2.50 at digi-key But i have seen them cheap if you can read
Chinese

This is Merry Xmas = 聖誕快樂

https://www.electro-tech-online.com/custompdfs/2010/12/cp2102.pdf
 
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The Prolific adapters are available on ebay in several configurations. Here's a picture of the module that's my current favorite. Search for "Mini USB To TTL / COM Converter Module build-in CP2102" sold by szdigitalsquare. The module is almost cheaper than the parts and brings out all of the serial handshake lines and 5 and 3.3 volt power. They're going for $6.49 at the moment.

The USB signals are also available on header pins if you want to use a different connector.

The board is 1" x 0.8"
 

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These are nice I just wish you could get them in p-dip FTDI usb-rs232 chip
 

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Jon i still prefer microchip because of great support... I know nothing of Prolific and since there ICs arent sold by Mouser i would be hesitant to buy them.. heh just my thoughts

Burt why not just buy one and place on SSOP/SOIC to DIP ?
 
The Prolific module is only offered as an alternative. Since none of the USB converters are offered in a DIP package, it's convenient for somebody who doesn't want to deal with small SMT parts. The cost for the module is $6.50 including shipping. At Digikey, it looks like FTDI chips in the 1 quantity are $4.50.

The MCP9800 is a nice part and I've played with it. The downside, unless the situation has changed, is that there are only Windows drivers and support for it.

I've used the Prolific chip in several different configurations from ebay and it's worked well for me, apart from having to track down some different drivers. I'm not trying to convince anybody to use it or change anybody's mind about it.
 
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heh... thats why im happy i learned SMT parts... SOIC is a BIG SMT so i find them easy to do... Pins are spaced so far apart compared to SSOP,QFN,TQFP,etc...

For the MCP2200 its just over $2 which is nice also. Cheap as heck...
Take a look at this picture. Everything needed to have a running converter... including USB connector..

mouser-jpg.49342
 

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Atom: how about even less?

$3.10
 

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BTW, d'you think I can stack a pair of .22uf caps, giving .44uf rather than the .47uf cap, and it will work ok? Kinda have the .22's in stock.

Same with the 470ohm resistors...I have some 270's in stock that ought to work ok. as LED dropping resistors.

How come u use 39pf for the Crystal caps....most of the 12Mhz crystals are around 18pf, which require 30pf caps.

Crystal Capacitor Formula (Parallel Mode)
-----------------------------------------
Let: CL = Crystal's load capacitance
CP = Circuit's parasitic capacitance
CI = Chip's input capacitance
C1 = Crystal oscillator capacitor 1
C2 = Crystal oscillator capacitor 2

Then: C1 = C2 = 2 * CL - (CP + CI)

Example: For a crystal with 18pF load capacitance (CL)
and assuming CP + CI = 5pF (typical), we have
C1 = C2 = 2 * 18 pF - 5pF = 31pF. We can then
use two 30 pF capacitors (closest standard
value).
 
I'm lazy that would mean one more step. I have a bunch of them I'm making a board that you can program a pic with this boot loader and then run Arduino code on the pic
 
Mosaic.. i never knew how to calc it. It works like a charm with 39pf caps heh... ill be sure to use that info tho :D

Also where did you learn this? I see there is a ton i still have to learn :)

Burt sounds like fun dude...

Why doesnt more people have a blog? Wordpress.com is free and easy as heck to use. Also host images for free! I recommend this to all. So many people have great ideas and i would love to see them all :D
 
BTW, d'you think I can stack a pair of .22uf caps, giving .44uf rather than the .47uf cap, and it will work ok? Kinda have the .22's in stock.

Same with the 470ohm resistors...I have some 270's in stock that ought to work ok. as LED dropping resistors.

How come u use 39pf for the Crystal caps....most of the 12Mhz crystals are around 18pf, which require 30pf caps.

Crystal Capacitor Formula (Parallel Mode)
-----------------------------------------
Let: CL = Crystal's load capacitance
CP = Circuit's parasitic capacitance
CI = Chip's input capacitance
C1 = Crystal oscillator capacitor 1
C2 = Crystal oscillator capacitor 2

Then: C1 = C2 = 2 * CL - (CP + CI)

Example: For a crystal with 18pF load capacitance (CL)
and assuming CP + CI = 5pF (typical), we have
C1 = C2 = 2 * 18 pF - 5pF = 31pF. We can then
use two 30 pF capacitors (closest standard
value).
I'm going to keep the table nice job Mosaic

Let me let in on something buy a bag of 22pf I have a 1000 of them works fine with most all crystals if you run into one that's not working grab some more out of the bag and change them .

A 22 pf can be off by a big bunch . Some as much as 40% And Im using ones made for crystals LOL
 
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It's a Christmas miracle!....I helped out other experienced members!:D

The formula is one of those nuggets I dug up on another forum somewherez. Was prob. lurking.

Burt, I have some 10pf,18pf and 22pf disc ceramics -thru hole. I guess I could use 22 pfs with some extra lead length to approach the 30pf.
 
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