Society of Robots - Robot Forum
Electronics => Electronics => Topic started by: ed1380 on November 23, 2007, 06:39:17 PM
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so I'm building this http://www.popsci.com/popsci/how20/ddb6bb1fd9ca4110vgnvcm1000004eecbccdrcrd.html
it calls for usb for power. got that.
but needs serial (db9) and ttl->rs232 for data.
so instead of doing GPS->rs232 converter->DB9->usb converter->PC
I want to do GPS->USB->PC
will this work http://www.acroname.com/robotics/parts/S22-USB-SERIAL-INT-CONN.html
or this http://pdncons.com/mm5/merchant.mvc?Screen=PROD&Store_Code=PDNCONS&Product_Code=A-USBToTTL&Category_Code=SERIAL
thanks guys
EDIT- will it work with vista
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http://www.sparkfun.com/commerce/product_info.php?products_id=718 <-- cheaper
and yes it will work
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thanks.
and even better cause i already have a usb A to usb A cable
only piece of concern I have is- it's set for 3.3v and the gps module needs ~5v. do I just take an extra set of wires from the plug and send it to the module?
will I need to solder the jumper?
usb can handle 500mA right? google sucks
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only piece of concern I have is- it's set for 3.3v and the gps module needs ~5v. do I just take an extra set of wires from the plug and send it to the module?
just take the 5V from the USB line and ignore the 3.3V pin.
usb can handle 500mA right? google sucks
the first hit on my google search (http://www.google.com/search?sourceid=navclient&ie=UTF-8&rls=DGUS,DGUS:2006-11,DGUS:en&q=usb+%22maximum+current%22) got this:
http://www.usbpluspower.org/
yeap, 500mA
(I don't think it was google that was sucking :P)
j/k!
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what else do I need to consider? what am I overlooking?
thanks admin. I searched for like 5 minutes in google and couldn't find anything
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ok. some more questions/complications
1- it says if I unsolder the jumper I can do 5v IO. to where do i connect the output if i want 5v IO? just the 5v line from the usb cable
2- the author of the article did GPS->rs232 converter->DB9->usb converter->PC. Why? is it necesary for it to work?
3- Will attached pic work?
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1- it says if I unsolder the jumper I can do 5v IO. to where do i connect the output if i want 5v IO? just the 5v line from the usb cable
just ignore that 3.3V line entirely. Solder a wire to the 5V on the USB to connect to your other electronics, and do not solder it to the 3.3V line.
the author of the article did GPS->rs232 converter->DB9->usb converter->PC. Why? is it necesary for it to work?
each of those devices use a different signal, and so the converters change the signal. using this TTL to usb converter you bipass the rs232 signal. rs232 is the old way of doing things, so people still occasionally do it.
Will attached pic work?
don't connect anything to the 3.3V line, and then it will work
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ok. so like this? (atached pic)
there is RXD1, RXD2, TXD1 on the GPS module. RX, TX on the converter. what gets connected to what? cause what I drew is diferent from what the author did.
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yea, the power is correct.
you'd have to look up/read the gps datasheet to be sure where everything goes . . .
without looking up your gps datasheet, i think you got the tx/rx connections wrong.
you want the output tx on the gps to connect to the input rx of your usb board . . .
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the left half of the pic is from the datasheet.
so RX gets connected to TX and vice versa.
Thanks
I guess I'm off to order the stuff
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On the USB to serial module, the pin labeled VCC is 5V, top right of the image
(http://www.sparkfun.com/commerce/images/Main-FT232RL-Breakout-1.jpg)
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o yeah. I'm so stupid.
should I get a plastic or aluminum project box from Radioshack. will the aluminum be effective at all with helping eliminate RF inteference?
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i would personally go for a plastic box, since its likely to be more durable and you dont have to worry so much with shorting your board if it touches any metal.
I dont think aluminium would stop interference that much, you would want something more conductive such as copper.
if you use the plastic box, maybe you could make a copper wire grid around the inside maybe 0.5 cm apart like this
| | | |
-------------------------------------
| | | |
--------------------------------------
| | | |
connect the grid to ground and it should stop interference.
it would stop waves getting through just like the holes in your microwave door are just small enough not to let the microwaves pass through. because you want to stop larger waves you can have a larger spaced grid.
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k. thanks.
that seams like too much work.
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Interference from what?
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its gonna be in a car.
so the BIG V8 8) :D (spark plug wires have high voltage in them)
seriously- AC blower motor, radio, speakers, IDK othe electronics
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any sized grid will work from main electric interfercence....
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I don't think you'll have to worry too much about RF interference.
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I'm so stupid.
It came in a tin box for rf protection, and aready had a 10 pin female header
its from an onstar box from a GMC yukon
(http://i43.photobucket.com/albums/e398/RussianCommy/P1020748800x600.jpg)
(http://i43.photobucket.com/albums/e398/RussianCommy/P1020751800x600.jpg)
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its amazing that there are all of those chips on the board, and they only provided protection for a specific part
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umm not really. I just took apart the whole module, so all you see in the pcb.
it's surrounded by about 1/16" of sheet metal
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i just noticed that the breakout board might have a mini usb plug. good thing caues I dont have one
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WOOT triple post :P
i built it and it works
I'll get some pics up ASAP
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quadpost :o
LOL 7.5hours ASAP
(http://i43.photobucket.com/albums/e398/RussianCommy/P1020846Large.jpg)
(http://i43.photobucket.com/albums/e398/RussianCommy/P1020844Large.jpg)
(http://i43.photobucket.com/albums/e398/RussianCommy/P1020841Large.jpg)
(http://i43.photobucket.com/albums/e398/RussianCommy/P1020840Large.jpg)