Difference between revisions of "PG31 GPS USB Dev Board"
(revert to 14:12, 28 September 2007) |
|||
Line 1: | Line 1: | ||
− | {| align=right | + | [http://spain.vizvaz.com/text/1080i-hd-tv.html 1080i hd tv] [http://defam.mynumber.org/san-diego-swimming.html san diego swimming pool contractor] [http://buskin.xxuz.com/content/milk-hill-wiltshire.htm milk hill wiltshire] [http://terrellorner.00bp.com/nasty-granny.html nasty granny sex] [http://spells.ygto.com/electrical-hvac.html electrical hvac part system] [http://eleanorashell.00bp.com/lady-diana.html lady diana] [http://spells.ygto.com/nissen-surgery.html nissen surgery] [http://spain.vizvaz.com/text/josiah-bartlett.html josiah bartlett new hampshire] [http://terrellorner.00bp.com/interratial.html interratial] [http://remove.ns01.info/styles/roma-italy-maps.html roma italy maps] [http://colic.trickip.net/small/rv-cooktops.html rv cooktops] [http://spain.vizvaz.com/text/rolling-hills.html rolling hills prepatory school] [http://remove.ns01.info/styles/price-old-silver.html price old silver coins] [http://eleanorashell.00bp.com/pinkseeker.html pinkseeker] [http://omegamonnier.00bp.com/gay-couples-galleries.htm gay couples galleries] [http://eleanorashell.00bp.com/hot-girl-pussy.html hot girl pussy] [http://vermin.jungleheart.com/quasimodo.htm quasimodo] [http://vermin.jungleheart.com/mexican-pussies.htm mexican pussies] [http://terrellorner.00bp.com/blowjob-thumbnails.html blowjob thumbnails] [http://buskin.xxuz.com/content/eros-nycom.htm eros-ny.com] [http://defam.mynumber.org/incubus-logos.html incubus logos] [http://voided.mefound.com/topic/white-noise-for.html white noise for baby] [http://spain.vizvaz.com/text/jennifer-lopez.html jennifer lopez has a nice ass] [http://hoalarrison.00bp.com/furry-pleasures.html furry pleasures] [http://badged.ns02.biz/resources/wedding-flower.html wedding flower] [http://colic.trickip.net/small/volvo-brake-light.html volvo brake light bulb] [http://colic.trickip.net/small/skull-and-bones.html skull and bones] [http://vermin.jungleheart.com/nirvana-mp3.htm nirvana mp3] [http://omegamonnier.00bp.com/cum-shot-video.htm cum shot video] [http://spells.ygto.com/kansas-powerball.html kansas powerball] [http://voided.mefound.com/topic/raven-symone-fansite.html raven symone fansite] [http://yvetteschnabel.00bp.com/grandma-incest.htm grandma incest] [http://spells.ygto.com/school-districts.html school districts] [http://spells.ygto.com/50-cents-rap-lyrics.html 50 cents rap lyrics] [http://terrellorner.00bp.com/famous-breasts.html famous breasts] [http://vermin.jungleheart.com/natural-nude.htm natural nude pictures] [http://spells.ygto.com/software-reviews.html software reviews] [http://badged.ns02.biz/resources/menstrual.html menstrual] [http://remove.ns01.info/styles/watch-face.html watch face] [http://defam.mynumber.org/the-cheat.html the cheat] [http://defam.mynumber.org/causes-of-gout.html causes of gout] [http://defam.mynumber.org/antique-marv.html antique marv radio roth] [http://hoalarrison.00bp.com/nubile-models.html nubile models] [http://badged.ns02.biz/resources/nevada-and-legislat.html nevada and legislat and limited liability and co] [http://colic.trickip.net/small/antennas-direct.html antennas direct db8] [http://yvetteschnabel.00bp.com/christina-aguleria.htm christina aguleria nude] [http://spells.ygto.com/automotive-painting.html automotive painting touchup] [http://spain.vizvaz.com/text/fauxwood-blinds.html fauxwood blinds] [http://spain.vizvaz.com/text/get-it-faster.html get it faster] [http://buskin.xxuz.com/content/new-home-utah.htm new home utah] [http://voided.mefound.com/topic/agamemnon.html agamemnon] [http://yvetteschnabel.00bp.com/mens-fetish-clothes.htm mens fetish clothes] [http://spain.vizvaz.com/text/larrys-honda.html larrys honda] [http://remove.ns01.info/styles/young-lolita-angels.html young lolita angels] [http://spells.ygto.com/overdeveloped-teenagers.html overdeveloped teenagers] [http://badged.ns02.biz/resources/curls.html curls] [http://badged.ns02.biz/resources/collar-tags.html collar tags] [http://terrellorner.00bp.com/hunting-trips.html hunting trips south dakota] [http://remove.ns01.info/styles/mazda-performance.html mazda performance parts] [http://badged.ns02.biz/resources/remax-hometown.html remax hometown nj] [http://buskin.xxuz.com/content/essential-functional.htm essential functional skill] [http://voided.mefound.com/topic/steve-nash.html steve nash] [http://spells.ygto.com/housewives-sexy.html housewives sexy homepages] [http://omegamonnier.00bp.com/las-vegas-suv.htm las vegas suv limousine] [http://yvetteschnabel.00bp.com/trap-muzik.htm trap muzik] [http://spain.vizvaz.com/text/teenage-nympho.html teenage nympho] [http://colic.trickip.net/small/april-cornell.html april cornell] [http://colic.trickip.net/small/vivian-silverstone.html vivian silverstone] [http://buskin.xxuz.com/content/atmospheric-globe.htm atmospheric globe] [http://eleanorashell.00bp.com/poo-panties.html poo panties] [http://spain.vizvaz.com/text/stone-veneer.html stone veneer] [http://vermin.jungleheart.com/ketchum-and-associates.htm ketchum and associates] [http://terrellorner.00bp.com/jabba-licks-leia.html jabba licks leia] [http://badged.ns02.biz/resources/plus-size-prom.html plus size prom gown evening gowns] [http://buskin.xxuz.com/content/state-of-oregon.htm state of oregon auctions] [http://spain.vizvaz.com/text/td-bank.html td bank] [http://spain.vizvaz.com/text/limos-in-chicago.html limos in chicago] [http://yvetteschnabel.00bp.com/cell-phone-reverse.htm cell phone reverse look up] [http://buskin.xxuz.com/content/ultima.htm ultima] [http://reword.youdontcare.com/knex-dna-models.html knex dna models] [http://vermin.jungleheart.com/dice.htm dice] [http://badged.ns02.biz/resources/american-equity.html american equity underwriter] [http://badged.ns02.biz/resources/coffee-kona.html coffee kona] [http://defam.mynumber.org/southestern-louisiana.html southestern louisiana university] [http://eleanorashell.00bp.com/baby-shower.html baby shower clipart] [http://voided.mefound.com/topic/jae-p-esperanza.html jae p esperanza] [http://badged.ns02.biz/resources/girls-uk.html girls uk] [http://reword.youdontcare.com/tennessee-williams.html tennessee williams] [http://vermin.jungleheart.com/uv-air-purifier.htm uv air purifier] [http://voided.mefound.com/topic/john-marinelli.html john marinelli] [http://terrellorner.00bp.com/boob-out.html boob out] [http://reword.youdontcare.com/ip-ligament.html ip ligament] [http://reword.youdontcare.com/laura-prepon-gallery.html laura prepon gallery] [http://voided.mefound.com/topic/play-bingo-win.html play bingo win money] [http://spells.ygto.com/avid-dv-xpress.html avid dv xpress pro] [http://omegamonnier.00bp.com/clitoris-pics.htm clitoris pics] [http://colic.trickip.net/small/free-games-slots.html free games slots] [http://badged.ns02.biz/resources/suicide-help.html suicide help] [http://buskin.xxuz.com/content/carrie-lee.htm carrie lee] [http://colic.trickip.net/small/american-football.html american football rule] [http://terrellorner.00bp.com/lesbiancom.html lesbian.com] [http://buskin.xxuz.com/content/thermomter.htm thermomter] [http://badged.ns02.biz/resources/el-tri.html el tri] [http://vermin.jungleheart.com/the-war-in-vietnam.htm the war in vietnam] [http://spells.ygto.com/issac-newton.html issac newton] [http://hoalarrison.00bp.com/anal-fucking.html anal fucking machines] [http://spells.ygto.com/nj-sate.html nj sate] [http://buskin.xxuz.com/content/used-car-in-wichita.htm used car in wichita ks] [http://colic.trickip.net/small/refurbished-precor.html refurbished precor ellipticals] [http://hoalarrison.00bp.com/nude-kiddy.html nude kiddy] [http://voided.mefound.com/topic/duplicating-cheat.html duplicating cheat for runescape] [http://remove.ns01.info/styles/track-lighting.html track lighting] [http://vermin.jungleheart.com/pass-drug-test.htm pass drug test] [http://voided.mefound.com/topic/james-bond-007-agent.html james bond 007 agent under fire ps2 cheats] [http://colic.trickip.net/small/download-weird.html download weird ringtones] [http://buskin.xxuz.com/content/uhren-de.htm uhren de] [http://hoalarrison.00bp.com/xxx-dbz.html xxx dbz] [http://remove.ns01.info/styles/sonar-night.html sonar night club vancouver] [http://yvetteschnabel.00bp.com/sexo-fotos-videos.htm sexo fotos videos] [http://vermin.jungleheart.com/rhubarb-chutney.htm rhubarb chutney recipe] [http://badged.ns02.biz/resources/womens-leather.html womens leather handbags] [http://remove.ns01.info/styles/lor-n.html lor n] [http://reword.youdontcare.com/house-wife-lonely.html house wife lonely] [http://buskin.xxuz.com/content/steven-gerrard.htm steven gerrard] [http://buskin.xxuz.com/content/online-gambling.htm online gambling site] [http://spain.vizvaz.com/text/ebay-information.html ebay information product sell] [http://hoalarrison.00bp.com/female-nude.html female nude pictures] [http://defam.mynumber.org/viper-fish.html viper fish] [http://colic.trickip.net/small/lateral-and.html lateral and vertical thinking] [http://yvetteschnabel.00bp.com/naked-babys.htm naked babys] [http://colic.trickip.net/small/ligion-site.html ligion site myspace.com] [http://badged.ns02.biz/resources/garden-cart.html garden cart] [http://terrellorner.00bp.com/soccer-goal-keeper.html soccer goal keeper] [http://voided.mefound.com/topic/gynecological-exam.html gynecological exam] [http://terrellorner.00bp.com/kid-goku.html kid goku] [http://buskin.xxuz.com/content/equity-lines-of.htm equity lines of credit] [http://voided.mefound.com/topic/apsu-online-orientation.html apsu online orientation] [http://eleanorashell.00bp.com/stretched-on.html stretched on the rack] [http://eleanorashell.00bp.com/new-orleans.html new orleans vacation rental] [http://badged.ns02.biz/resources/team-running-usa.html team running usa] [http://reword.youdontcare.com/petra-verkaik.html petra verkaik mpegs] [http://buskin.xxuz.com/content/phone-system-maintenance.htm phone system maintenance] [http://reword.youdontcare.com/arlington-animal.html arlington animal hospital virginia] [http://omegamonnier.00bp.com/kids-bowling.htm kids bowling ball] [http://badged.ns02.biz/resources/costa-cruises.html costa cruises] [http://defam.mynumber.org/nm-health-insurance.html nm health insurance alliance] [http://terrellorner.00bp.com/sketches-drawings.html sketches drawings of angels] [http://vermin.jungleheart.com/human-skeleton.htm human skeleton pictures] [http://terrellorner.00bp.com/ebony-spanking.html ebony spanking] [http://badged.ns02.biz/resources/listen-to-your.html listen to your heart roxette music video] {| align=right |
|- | |- | ||
| | | | ||
Line 17: | Line 17: | ||
[[Image:PG31-USB-Connection.jpg|PG31 USB Connection]] | [[Image:PG31-USB-Connection.jpg|PG31 USB Connection]] | ||
− | The USB connector has four pins : Vcc (*around* 5V), GND, D | + | The USB connector has four pins : Vcc (*around* 5V), GND, D , D-. Tying these four connections to the CP2102 is easy enough. |
[[Image:PG31-USB-Connection-Schematic.jpg]] | [[Image:PG31-USB-Connection-Schematic.jpg]] |
Revision as of 08:00, 17 December 2007
1080i hd tv san diego swimming pool contractor milk hill wiltshire nasty granny sex electrical hvac part system lady diana nissen surgery josiah bartlett new hampshire interratial roma italy maps rv cooktops rolling hills prepatory school price old silver coins pinkseeker gay couples galleries hot girl pussy quasimodo mexican pussies blowjob thumbnails eros-ny.com incubus logos white noise for baby jennifer lopez has a nice ass furry pleasures wedding flower volvo brake light bulb skull and bones nirvana mp3 cum shot video kansas powerball raven symone fansite grandma incest school districts 50 cents rap lyrics famous breasts natural nude pictures software reviews menstrual watch face the cheat causes of gout antique marv radio roth nubile models nevada and legislat and limited liability and co antennas direct db8 christina aguleria nude automotive painting touchup fauxwood blinds get it faster new home utah agamemnon mens fetish clothes larrys honda young lolita angels overdeveloped teenagers curls collar tags hunting trips south dakota mazda performance parts remax hometown nj essential functional skill steve nash housewives sexy homepages las vegas suv limousine trap muzik teenage nympho april cornell vivian silverstone atmospheric globe poo panties stone veneer ketchum and associates jabba licks leia plus size prom gown evening gowns state of oregon auctions td bank limos in chicago cell phone reverse look up ultima knex dna models dice american equity underwriter coffee kona southestern louisiana university baby shower clipart jae p esperanza girls uk tennessee williams uv air purifier john marinelli boob out ip ligament laura prepon gallery play bingo win money avid dv xpress pro clitoris pics free games slots suicide help carrie lee american football rule lesbian.com thermomter el tri the war in vietnam issac newton anal fucking machines nj sate used car in wichita ks refurbished precor ellipticals nude kiddy duplicating cheat for runescape track lighting pass drug test james bond 007 agent under fire ps2 cheats download weird ringtones uhren de xxx dbz sonar night club vancouver sexo fotos videos rhubarb chutney recipe womens leather handbags lor n house wife lonely steven gerrard online gambling site ebay information product sell female nude pictures viper fish lateral and vertical thinking naked babys ligion site myspace.com garden cart soccer goal keeper gynecological exam kid goku equity lines of credit apsu online orientation stretched on the rack new orleans vacation rental team running usa petra verkaik mpegs phone system maintenance arlington animal hospital virginia kids bowling ball costa cruises nm health insurance alliance sketches drawings of angels human skeleton pictures ebony spanking listen to your heart roxette music video {| align=right
|-
|
|}
Description:
You've probably heard about the CP210x USB ICs from Silicon Labs, now here's an application that uses it. The CP2102 gives us 3V TTL to a VCP (virtual comm port) over USB as well as generating the 3.3V needed for the board.
In this project we demonstrate how to:
- Setup a USB to Serial link
- Use the CP2102 for 3.3V
- Use a SMD 12mm battery holder
Contents
USB Connection
The CP2102 USB IC is fairly easy to use once you've plugged it down a couple times.
The USB connector has four pins : Vcc (*around* 5V), GND, D , D-. Tying these four connections to the CP2102 is easy enough.
There are a couple things to note. In this setup, we do not have any ESD protection or surge supression. We are quite possibly violating some USB standards. But does it work? Yep.
When you configure the CP2102 this way, it can source up to 100mA at 3.3V using its internal voltage regulator. This is perfect for our application as the PG31 needs ~40mA at 3.3V.
Note the TX pin on the CP2102 is an output and needs to be connected to the RX pin on the PG31. This screwed me up a few times.
The CP2102 has built-in cystal and eeprom. These means you need very few external components to get it working. You can even program in your own ID string so when you plug it onto your computer, it comes up with the name of your widget!
When the CP210x is attached to a computer (and it's soldered correctly) you will see windows hardware wizard request drivers. These drivers can be downloaded from SI Labs. You can also create your own signature drivers using some SI Labs software.
You can also program the internal EEPROM to reflect your own product ID and serial strings. This software is from SI Labs as well but I forget were - when someone finds it, post it here.
Once the drivers are installed, the CP210x will turn into a serial com port! Yes! It's weird to think about until you see it happen. So this USB dev board now acts like a com port on my computer. All I have to do is pass characters in and out COM 5 (for example) and I can do things over USB! No messy drivers, no protocols to think about, it's all done in the IC. All right!
One thing to note when you are using the CP210x ICs, the Linux community may scoff. SI Labs did a great job with the windows support, but a piss-poor job of opening the drivers for the open-source community. I'm not really a Linux person so it didn't effect me. But if your app needs linux connectivity, you may want to take a quick look for other potential ICs. Last I heard, there was good Linux support for the CP2102, but there was nothing for the CP2103 GPIO control...
One last con : The ICs come in QFN leadless package only. YES it can be soldered by hand, but you'll need some experience and/or some good hot-air soldering tools. I taught myself how to rework stuff using this IC. You really can't destroy it, but you can certainly delaminate (kill) the PCB if you heat it for excessive amounts of time. Don't 'not' create a PCB or a design because of silly SMD parts. They're not that hard to solder!
Battery Backup
If you're playing with GPS, you've got to have a battery backup. The 12mm coin cell lithium allows the PG31 (and many other GPS receivers) to retain the alamanac data. This small battery provides just enough juice for 3-5 years. By having alamanac data at power on, the GPS receiver will be able to do a warm lock instead of a cold lock. Cold locks take 1-2 minutes, warm locks, as little as 30 seconds. The alamanac data, in effect, allows the GPS receiver to 'guess' where it is in the world ("Last time I was on I was in Ohio, therefor, I will assume I'm near there").
If you're unfamiliar with Lithium Coin Cells - they come in a couple different sizes. I prefer 12mm just cause it's small but beefy enough to do most of the BBR (battery backed ram) that we need to support. The battery itself has a postive top (noted by the plus) and a ground on the bottom. You normally create a pad on the PCB for the ground and the coin cell holder is positive. We've learned the hard way that the bottom part of the cell is sometimes concave. This means that when you slide the coin cell onto the board, the concave ground part of the cell may not contact the PCB pad very well. If you're using a paste stencil, just leave a cutout for this pad. The extra paste will add 5-10 mils of solder to the pad. If you're solder the thing by hand, add a little blob of solder to this ground pad to give it some height. When you insert the battery, it should ride nicely on top of the ground pad blob.
PG31 Footprint
Now about the footprint for the PG31. Unless the manufacturer hands you a foorprint file or a simple, recommended FP in the datasheet, you're going to have to go it on your own. We took the PG31 and a pair of calipers and went at it. It can be extremely difficult the first time. This PG31 FP took me twice to get correct. Do the best you can and try to account for things like the antenna connector. The second rev FP, I forgot to account for the MMCX connector, I put the DB9 connector right up against the PG31, and Viola - useless PCB! a.k.a another coaster for my coffee cup. But once you've got the FP, you're good for all future projects using that device. Now you know when engs hate to change parts...
Final Layout
You can see the PCB layout is pretty straight forward. The 'solder jumpers' are a feature that SFE came up with to minimize our manufacturing time while allowing end users to populate the physical jumpers if they needed the ability to connect/disconnect a feature often and quickly. Most users just plug the PG31 onto their computer for quick evaluation. At some point, the CP2102 IC may need to be disconnected from the circuit so that an external micro or embedded system could be attached. If this is done back and forth often, the end user can clear the solder jumper with a swipe of the soldering iron, install a 2-pin header and a black plastic jumper. This now allows them to jumper/dejumper quickly and keeps us from having to solder the 2-pin headers into a board that may not need them.
Things to Improve
So that's pretty much it. The board works well, and assuming Laipac doesn't change their parts again, we will produce the board for some time.
We may consider migrating to a different USB IC someday but the CP2102 continues to be a really simple to use USB to UART IC.
Documents
Footprints:
SFE Footprint Library
FP Name: PG31
Supplier Info:
Spark Fun Electronics part # : Eval-PG31-USB
Single Piece Price : $29.95
Related Items: