Difference between revisions of "PG31 GPS RS232 Dev Board"

From OpenCircuits
Jump to navigation Jump to search
m (Reverted edits by 200.58.228.85 (Talk); changed back to last version by 71.141.115.29)
Line 1: Line 1:
[http://indianaoutfitters.com/s/info/tmp/hehcux.html taylor building crystal city virginia] [http://smallbizbohol.com/democatalog/images/baner/lnrvvm.html online business tax filing] [http://indianaoutfitters.com/s/info/tmp/aqcoxm.html starting tomato plant] [http://asie-voyages.com/upload/images/lens/egmasg.html 1 card gb memory sandisk] [http://www.biblored.org.co/agenda_actividades/programas/images/tjqgjm.html lietuviskas radijas] [http://tarsierfoundation.org/content/license/rplqgt.html marks on china made in japan] [http://www.biblored.org.co/agenda_actividades/programas/images/vtsohu.html seductive song] [http://xuccco.org/themes/AT-Green3/lhbuoi.html post impressionists art] [http://xuccco.org/themes/AT-Green3/hdjelg.html american sign language teachers association] [http://panties-pictures.com/free/lib/temp/vdvgkq.html torrent microsoft office 2004] [http://tarsierfoundation.org/content/license/dipckx.html 8th grade math problem] [http://smallbizbohol.com/democatalog/images/baner/tiucta.html thin film deposition equipment] [http://bluespringsbmx.com/4IMAGES/data/media/10/tmp/jbjjef.html almost peed] [http://panties-pictures.com/free/lib/temp/dqeowo.html india map north east] [http://xuccco.org/themes/AT-Green3/golfnb.html random jpegs] [http://panties-pictures.com/free/lib/temp/gbhosa.html southern scene] [http://www.redacademica.edu.co/manejocorreo/Cliente/cache/tdrcdt.html pen pals international email free] [http://www.lewakins.com/sr/images/degcno.html nasa dryden] [http://indianaoutfitters.com/s/info/tmp/dhfftn.html pro tect security] [http://cvscaft-tcc.edu.ph/gallery/uploads/cache/ochtis.html new york knicks jerseys] [http://smallbizbohol.com/democatalog/images/baner/idqbsm.html we buy computer parts] [http://roycemotor.com/carpics/cache/gvbbjf.html stark county home sales] [http://www.redacademica.edu.co/manejocorreo/Cliente/cache/fqmcuf.html jackals pictures] [http://indianaoutfitters.com/s/info/tmp/ruftff.html 1 gb pc2700 ram] [http://www.biblored.org.co/agenda_actividades/programas/images/btpbhq.html rob thomas new single listen] [http://asie-voyages.com/upload/images/lens/gbdmtv.html taipei towers] [http://asie-voyages.com/upload/images/lens/pbloxv.html transportation planning minnesota] [http://ankelia-nature.com/catalogues/catalogues/ftatlj.html atlanta fun facts] [http://www.lewakins.com/sr/images/bhachg.html pc comparison guide] [http://lumayagrealty.com/catalog/images/pics/frxvql.html muhammads death] [http://coastguard.gov.ph/content.old/license/gitlpe.html telecommunication tyco] [http://indianaoutfitters.com/s/info/tmp/trjxer.html lyrics for give it all rise against] [http://www.biblored.org.co/agenda_actividades/programas/images/mokpru.html shell canada locations] [http://lumayagrealty.com/catalog/images/pics/drfahd.html 2000 olympic games sydney] [http://roycemotor.com/carpics/cache/jnlemk.html residential wind generators] [http://bluespringsbmx.com/4IMAGES/data/media/10/tmp/xjwlse.html announcement birth ohio] [http://bluespringsbmx.com/4IMAGES/data/media/10/tmp/lldcex.html american express corporate travel sydney] [http://tarsierfoundation.org/content/license/kumplh.html marie joseph] [http://talentmodeles.com/mannequin/images/cache/iicvdn.html programs to make business cards] [http://xuccco.org/themes/AT-Green3/vqcnvg.html project on electronic] [http://hoosierfishing.com/phpBB/images/avatars/avatar/bbakkf.html nickel ceiling lights] [http://lumayagrealty.com/catalog/images/pics/nmbqpu.html quicken registration file] [http://bluespringsbmx.com/4IMAGES/data/media/10/tmp/wvsqkf.html limousine chicago] [http://panties-pictures.com/free/lib/temp/bnunix.html prime card] [http://www.lewakins.com/sr/images/erlkpl.html interstate credit collection] [http://lumayagrealty.com/catalog/images/pics/dwkkak.html man leather key case] [http://panties-pictures.com/free/lib/temp/rblbvk.html remax commercial brokerage] [http://ankelia-nature.com/catalogues/catalogues/laxbkg.html train baltimore new york] [http://lumayagrealty.com/catalog/images/pics/qqnwxh.html large cutting mat] [http://tarsierfoundation.org/content/license/qpvdju.html after dark mac os x] [http://lumayagrealty.com/catalog/images/pics/jkxjpr.html what is private equity company] [http://roycemotor.com/carpics/cache/usqmqk.html young katie] [http://www.sedbogota.edu.co/FINANCIERA/temp/tmp/oxoupk.html i could never leave your beautiful eyes] [http://talentmodeles.com/mannequin/images/cache/ugjead.html mexico vacation] [http://asie-voyages.com/upload/images/lens/chnjfq.html leadership journal magazine] [http://roycemotor.com/carpics/cache/lchtjc.html maui condos rent] [http://tch-voyages.com/documents/prague/896/nidpsr.html residential wind generators] [http://tarsierfoundation.org/content/license/nmpcgh.html wild child motorcycle] [http://asie-voyages.com/upload/images/lens/vjecxu.html william m mercer inc] [http://xuccco.org/themes/AT-Green3/orutts.html judaica nyc] [http://panties-pictures.com/free/lib/temp/ipckoa.html act library services technology] [http://cvscaft-tcc.edu.ph/gallery/uploads/cache/wmdgge.html iden phones motorola] [http://asie-voyages.com/upload/images/lens/uspmqx.html lori singer] [http://xuccco.org/themes/AT-Green3/aueqcs.html arkansas news channels] [http://cvscaft-tcc.edu.ph/gallery/uploads/cache/tksdok.html osborn high school] [http://bluespringsbmx.com/4IMAGES/data/media/10/tmp/orxglt.html 15 apr month o] [http://panties-pictures.com/free/lib/temp/blmnjf.html elder estate real] [http://lumayagrealty.com/catalog/images/pics/eebhqt.html knife and gun finishing supply] [http://www.redacademica.edu.co/manejocorreo/Cliente/cache/muqckw.html x scale processors] [http://bluespringsbmx.com/4IMAGES/data/media/10/tmp/djxbln.html interface parameter tcpip] [http://tarsierfoundation.org/content/license/jgfdbi.html apartment finder parking] [http://indianaoutfitters.com/s/info/tmp/kabtjw.html www aged] [http://indianaoutfitters.com/s/info/tmp/isbuuu.html mark protection trade] [http://roycemotor.com/carpics/cache/sdeusk.html oh my goodness cookies] [http://www.biblored.org.co/agenda_actividades/programas/images/wntxea.html labour cabinet] [http://smallbizbohol.com/democatalog/images/baner/xtxfwg.html west coast porn] [http://cvscaft-tcc.edu.ph/gallery/uploads/cache/maucog.html music note player] [http://panties-pictures.com/free/lib/temp/gektxi.html rotten pictures] [http://bluespringsbmx.com/4IMAGES/data/media/10/tmp/vvjthp.html picture pomegranates] [http://asie-voyages.com/upload/images/lens/euoajt.html image mixer sony software] [http://hoosierfishing.com/phpBB/images/avatars/avatar/puocjk.html employer benefit services] [http://bluespringsbmx.com/4IMAGES/data/media/10/tmp/xjfpqj.html post office business] [http://tch-voyages.com/documents/prague/896/wodibt.html moen part] [http://smallbizbohol.com/democatalog/images/baner/goeukh.html meningitis in children symptoms] [http://panties-pictures.com/free/lib/temp/rbabic.html learn about dna] [http://www.biblored.org.co/agenda_actividades/programas/images/bpproc.html man sex stories] [http://smallbizbohol.com/democatalog/images/baner/livdil.html medical terminology a living language] [http://www.sedbogota.edu.co/FINANCIERA/temp/tmp/cpfnpu.html exel global freight management] [http://www.lewakins.com/sr/images/hpiths.html ashlee cum] [http://roycemotor.com/carpics/cache/snbaap.html syntactically correct] [http://www.norcab.com.au/joeavatiforum/templates/cache/scpfnw.html world war 2 british militaria] [http://roycemotor.com/carpics/cache/pfsvhc.html introduction to geography] [http://smallbizbohol.com/democatalog/images/baner/fvjdbl.html eight track tapes] [http://tch-voyages.com/documents/prague/896/htwbtt.html pelagic environment] [http://www.hdac.org/hdfaq/faq/isgjif.html washington state homeschool] [http://bluespringsbmx.com/4IMAGES/data/media/10/tmp/vqxnhd.html ohio motor vehicle reports] [http://roycemotor.com/carpics/cache/uddlea.html age cheryl crow] [http://www.hdac.org/hdfaq/faq/fbwgss.html angiotensin converting enzyme level] [http://indianaoutfitters.com/s/info/tmp/uooqkn.html juniors shopping online] [http://bluespringsbmx.com/4IMAGES/data/media/10/tmp/igwixt.html the middle colonies economy] [http://asie-voyages.com/upload/images/lens/igwqpp.html software vcd cutter] [http://xuccco.org/themes/AT-Green3/cpnqnm.html north german plains] [http://www.youthfitnesssolutions.com/FTP1/page9/txsblw.html pneumonia definition] [http://www.redacademica.edu.co/manejocorreo/Cliente/cache/chthnf.html online program rn] [http://tarsierfoundation.org/content/license/aaecem.html expressiveness] [http://roycemotor.com/carpics/cache/dagldc.html real player content live] [http://www.hdac.org/hdfaq/faq/uuewsj.html new laser weapon] [http://talentmodeles.com/mannequin/images/cache/tmobik.html texas a m university athletics] [http://lumayagrealty.com/catalog/images/pics/fxgjko.html what type of fruit is a love apple] [http://xuccco.org/themes/AT-Green3/dcokfv.html peace and reconciliation funding] [http://roycemotor.com/carpics/cache/esspiu.html per capita income growth] [http://www.biblored.org.co/agenda_actividades/programas/images/bdkurh.html relationship specialists] [http://www.youthfitnesssolutions.com/FTP1/page9/wfxfog.html ottawa yellow pages canada] [http://www.youthfitnesssolutions.com/FTP1/page9/bhwetr.html volume control bar] [http://smallbizbohol.com/democatalog/images/baner/mheqiv.html star academy 3] [http://www.biblored.org.co/agenda_actividades/programas/images/vfjmcl.html pro tect security] [http://talentmodeles.com/mannequin/images/cache/jgolen.html ted williams enterprise] [http://www.redacademica.edu.co/manejocorreo/Cliente/cache/utqtqv.html acura logo] [http://www.lewakins.com/sr/images/kuiejx.html aol check mail online] [http://cvscaft-tcc.edu.ph/gallery/uploads/cache/vvxqte.html encore action] [http://cvscaft-tcc.edu.ph/gallery/uploads/cache/mxpkce.html interview with the vampire the movie] [http://bluespringsbmx.com/4IMAGES/data/media/10/tmp/uevshp.html telegraph forum] [http://www.sedbogota.edu.co/FINANCIERA/temp/tmp/bnqunx.html along came mary] [http://panties-pictures.com/free/lib/temp/wrmquj.html pictures of the band fall out boy] [http://xuccco.org/themes/AT-Green3/tebqtx.html mba admission essay sample] [http://roycemotor.com/carpics/cache/vfsbhc.html relief printing artists] [http://bluespringsbmx.com/4IMAGES/data/media/10/tmp/hbbagr.html test multiple intelligence] [http://tarsierfoundation.org/content/license/vglhjx.html upper deck 2003] [http://www.lewakins.com/sr/images/ucnexl.html english french services translation] [http://bluespringsbmx.com/4IMAGES/data/media/10/tmp/ikikol.html java read string from console] [http://www.hdac.org/hdfaq/faq/hmlclq.html poker bonus code best] [http://www.youthfitnesssolutions.com/FTP1/page9/touaek.html 2.0 award web] [http://indianaoutfitters.com/s/info/tmp/qxjgwx.html treatment for psychosis] [http://bluespringsbmx.com/4IMAGES/data/media/10/tmp/qsxhvr.html monologue play] [http://www.sedbogota.edu.co/FINANCIERA/temp/tmp/inmhbv.html tile discounters] [http://tch-voyages.com/documents/prague/896/jfecva.html truck floor mates] [http://indianaoutfitters.com/s/info/tmp/mgmmkg.html market listing service] [http://indianaoutfitters.com/s/info/tmp/diqcak.html raytheon appliances] [http://bluespringsbmx.com/4IMAGES/data/media/10/tmp/nuwxbs.html the truman show trumans fathers name] [http://talentmodeles.com/mannequin/images/cache/jqhkxj.html logical star topology] [http://asie-voyages.com/upload/images/lens/swkdic.html protected area] [http://hoosierfishing.com/phpBB/images/avatars/avatar/cfqbkt.html sacramentos] [http://cvscaft-tcc.edu.ph/gallery/uploads/cache/iktogx.html single christian mothers] [http://smallbizbohol.com/democatalog/images/baner/fuvwww.html rights under the fair credit reporting] [http://www.lewakins.com/sr/images/wgxebp.html suicide survey teen] [http://ankelia-nature.com/catalogues/catalogues/mminww.html lady pearl] [http://hoosierfishing.com/phpBB/images/avatars/avatar/hlrtnp.html soft water system] [http://www.lewakins.com/sr/images/mblaja.html text books for college] [http://lumayagrealty.com/catalog/images/pics/robtxd.html lexus interior part] [http://coastguard.gov.ph/content.old/license/srifpp.html texas buyer agent] [http://www.youthfitnesssolutions.com/FTP1/page9/ggbtha.html process piping and design] [http://ankelia-nature.com/catalogues/catalogues/pqupxf.html special operations training association] [http://www.biblored.org.co/agenda_actividades/programas/images/nfjodm.html spoken word atlanta] [http://panties-pictures.com/free/lib/temp/dnufqv.html sony record nashville] [http://www.biblored.org.co/agenda_actividades/programas/images/wcibup.html amato salvatore] [http://www.sedbogota.edu.co/FINANCIERA/temp/tmp/kahvcf.html edge phoenix radio] [http://ankelia-nature.com/catalogues/catalogues/odstgf.html stars in circles] [http://www.redacademica.edu.co/manejocorreo/Cliente/cache/subwch.html west palm beach airport car rentals] [http://ankelia-nature.com/catalogues/catalogues/vmxnep.html masturbation picture tip] [http://www.sedbogota.edu.co/FINANCIERA/temp/tmp/gcmbrj.html without ever knowing] [http://smallbizbohol.com/democatalog/images/baner/unpaog.html 18k chain] [http://lumayagrealty.com/catalog/images/pics/suoboi.html laptop hard drive uk] [http://www.biblored.org.co/agenda_actividades/programas/images/qprgtu.html population growth in the philippines] [http://smallbizbohol.com/democatalog/images/baner/vajijb.html architectural symbol library] [http://www.sedbogota.edu.co/FINANCIERA/temp/tmp/lsehow.html elected band] [http://roycemotor.com/carpics/cache/cbsvsg.html motorola radios los angeles] [http://smallbizbohol.com/democatalog/images/baner/mavajp.html list of exits] [http://panties-pictures.com/free/lib/temp/iwwpfb.html practical nurse scope of practice] [http://talentmodeles.com/mannequin/images/cache/jwlujq.html stock quotes for wal mart] [http://www.redacademica.edu.co/manejocorreo/Cliente/cache/jlnxdj.html v bulletin] [http://www.biblored.org.co/agenda_actividades/programas/images/nenkki.html official rules of poker] [http://www.sedbogota.edu.co/FINANCIERA/temp/tmp/ucqweh.html mpeg to dvd download] [http://www.norcab.com.au/joeavatiforum/templates/cache/bcigdc.html man leather key case] [http://www.biblored.org.co/agenda_actividades/programas/images/nhwtaw.html ancient rome bath houses] [http://cvscaft-tcc.edu.ph/gallery/uploads/cache/klkwxs.html state governments india] [http://www.norcab.com.au/joeavatiforum/templates/cache/acaksb.html presentacion de una empresa] [http://xuccco.org/themes/AT-Green3/jupuvq.html ny return status tax] [http://tarsierfoundation.org/content/license/wolhhb.html sandy bay first nations] [http://roycemotor.com/carpics/cache/pfossb.html enter matrix cheats pc] [http://roycemotor.com/carpics/cache/jlhuhe.html pick up big] [http://roycemotor.com/carpics/cache/stitgc.html software for palm one] [http://roycemotor.com/carpics/cache/ehxvia.html the small hours tabs] [http://panties-pictures.com/free/lib/temp/jcigad.html preferred packaging] [http://cvscaft-tcc.edu.ph/gallery/uploads/cache/ghhdha.html attorney houston] [http://ankelia-nature.com/catalogues/catalogues/pullhu.html political regimes] [http://cvscaft-tcc.edu.ph/gallery/uploads/cache/bfporc.html texas buyer agent] [http://lumayagrealty.com/catalog/images/pics/cxdlmm.html american driving records] [http://cvscaft-tcc.edu.ph/gallery/uploads/cache/uxinor.html struggles quotes] [http://indianaoutfitters.com/s/info/tmp/ggbhfg.html labour cabinet] [http://coastguard.gov.ph/content.old/license/tjpbgu.html internet explorer connections registry] [http://panties-pictures.com/free/lib/temp/urgsla.html late night shopping melbourne] [http://www.biblored.org.co/agenda_actividades/programas/images/ipsrsh.html physical feature of a rain forest] [http://www.sedbogota.edu.co/FINANCIERA/temp/tmp/mcvwbi.html sumitomo industry] [http://panties-pictures.com/free/lib/temp/aanres.html marjorie wilson artist] [http://www.hdac.org/hdfaq/faq/btvoki.html my fair lady cast of characters] [http://panties-pictures.com/free/lib/temp/exhghm.html nicky hilton style] [http://www.lewakins.com/sr/images/csvgin.html optical density scanner] [http://www.sedbogota.edu.co/FINANCIERA/temp/tmp/bljlwx.html win sock fix] [http://ankelia-nature.com/catalogues/catalogues/meqmbg.html letter hearts] [http://asie-voyages.com/upload/images/lens/thuuos.html lyric good times television show] {| align=right
+
{| align=right
 
|-
 
|-
 
|  
 
|  

Revision as of 07:34, 12 November 2007

PG31 RS232 Dev Board

Description:
Getting information from your project to your computer can be difficult at first. Once you discover how to setup an RS232 connection, it's really just cut-and-paste for future projects.

In this project we demonstrate how to:

  • Setup an external power supply
  • Setup 3.3V to RS232 circuit
  • Complex PG31 GPS footprint

Power Regulation

First we will start with a simple adjustable voltage regulation circuit:

PG31 Power Supply

Please note this is a relatively compact SMD version of the power supply. This can easily be obtained with through-hole components using a breadboard. Here is the schematic:

PG31-PowerSupply-Schematic.jpg

Now let's discuss what's going on here. The barrel jack (J1) is a basic 5.5mm OD 2.1mm ID type jack. We get an unregulated 9-13V out of the wall wart.

The D3 large diode MBRA140 is for reverse protection. It can handle up to 1A and prevents damage to the board if a center-negative wallwart is attached. This diode will cause a ~0.5V drop from whatever the wall-wart is outputting.

C2 (10uF Tantalum Capacitor in this case) is a basic decoupling cap. 10-100uF is adequate but should be rated for 15-25V.

U1 is the LM317 (or LM1117 in SMD form) adjustable voltage regulator. It will take in some larger voltage and output a set voltage. The output voltage is set with two external resistors. R1 is historically 240 and value for R2 is different for different required output voltages. In our case, we want 3.3V out of the regulator, so R2 is set to 715. The LM317 is good because it is variable, the SOT-223 package is nice becuase it can take a relatively large voltage on the input (25V max I believe?) and has decent heat dissapation.

C1 and C3 are decoupling caps that help clean up the output transcients and noise.

J2 is just a two pin polarized header so that you can either 'steal' 3.3V from the board to power other boards, or have other boards power this board without the need for the external wall wart.


RS232 Interface

So we've got a nice clean output of 3.3V from the regulator, let's look at the RS232 connection:

PG31 Serial Connection

This shows the DB9 connector (also known as a D-Sub 9-pin connector), serial cable, and MAX3232 IC and charge pump caps (all SMD, again, can be done with PTH components). Here is the schematic:

PG31-SerialConnection-Schematic.jpg

Now read-up on the MAX232 IC. It could be the most common IC out there, at least for the embdded world. This IC will have many different model names (ICL232 for example) but all do the same thing, and will most likely have identical pin-outs. This IC is used to take low voltage signals from your micro or PIC or ARM or whatever, and converts those low-voltage signals to higher-voltage signals that the computer can understand. The voltage levels on TTL are also inverted for RS232 so the MAX232 takes care of that as well!

The MAX232 takes in TTL signals and sends out RS232 signals. It also takes the RS232 signals from the computer and outputs TTL signals to whatever microcontroller you are using. How does it do this magic? With charge pump capacitors. You'll notice four 0.1uF caps attached to the MAX3232. If you're reading closely, you'll also notice we have a MAX3232 not the MAX232. Difference:

  • MAX232 must be powered with 5V and converts 5V TTL<->RS232
  • MAX3232 can be powered from 3V to 5V and converts it to RS232

So in this application, the GPS unit is running at 3.3V. If we were to send 5V TTL to it, it would be damaged! So we must use the lower voltage MAX3232 part. No big deal, it's functionally identical to the MAX232. From here on out, I will only refer to the MAX232.

When you first view the MAX232 component, it can be a bit confusing. The pins label T1/T2 are the transmit channels (MAX232 has 2 TX channels and 2 RX channels). T1In/T2In will take *in* TTL and send *out* RS232 out T1Out/T2Out. So for our purposes, we need to connect the GPS unit's serial TX pin to the T1In pin of the MAX232. So when the GPS unit outputs some 3.3V TTL signals, these signals will be converted into RS232 and sent to the computer (TX1Out is connected to pin 2 on the DB9 connector).

Finally, when the computer needs to send info to the GPS unit, it will send RS232 signals down the serial cable, on pin 3 of the serial cable/DB9 connector to R1In of the MAX232. This RS232 signal will be converter to TTL and sent out the R1Out pin. This TTL signal is connected to the RX pin on the GPS unit. Voila.

I can't tell you how many times I've crossed TX and RX on different projects. Sit down, think about it, and once you've got it wired correctly, cut and paste into future projects.


PG31 Footprint

PG31-Footprint.jpg

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 why engineers hate to change parts...


Final Layout

PG31-Layout.jpg

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 MAX232 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.


Documents

PG31-RS232 Schematic

PG31-RS232 Protel File

PG31-RS232 Gerber Files

Footprints: SFE Footprint Library

FP Name: PG31

Supplier Info: Spark Fun Electronics part # : Eval-PG31-RS232
Single Piece Price : $29.95

Related Items: