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Can't find prop, need help. — Parallax Forums

Can't find prop, need help.

SexieWASDSexieWASD Posts: 41
edited 2009-09-23 01:11 in Propeller 1
It's me again, I got my PCB in the other day and got everything soldered to it fine (easier than it looked, and kinda fun), but I can't get the prop tool to recognize it. I keep getting the same "no propeller chip found on any serial port" message. It recognizes my uoled-96-prop when that is plunged in though.


IMAGE OF PCB FILE




I have tried both with and without the pull-up resistors on the rx, tx, and res lines.

Any ideas on why it doesn't work? I'm stumped but I am sure its just a stupid mistake, I am new to all of this.

I've attached the PCB file, it's for ExpressPCB if anyone uses it.

Comments

  • SRLMSRLM Posts: 5,045
    edited 2009-09-13 07:09
    Look at the order of the lines on the Prop plug. Ground is supposed to be on the outside.

    www.parallax.com/Portals/0/Downloads/docs/prod/prop/32200-32201-PropClipPlug-v1.3.pdf
  • SexieWASDSexieWASD Posts: 41
    edited 2009-09-13 12:08
    I forgot to say I'm using a μUSB-CE5 from 4d Systems, it a FT232RQ chip, and I've used it with a dip propeller and it worked ok.

    I have the BOEn pin tied to VDD, could that cause the problem?

    Post Edited (SexieWASD) : 9/13/2009 1:49:25 PM GMT
  • Mike GreenMike Green Posts: 23,101
    edited 2009-09-13 14:00
    Read the description of the BOEn and RESn pins in the Propeller datasheet. If you tie BOEn to Vdd, you don't have the built-in weak pullup on RESn and you'd have to have an external pullup.
  • SexieWASDSexieWASD Posts: 41
    edited 2009-09-13 14:25
    I just tried with a pullup on just the RESn line, but no luck, I think that I have made a much bigger mistake. I have a few pins for 5V rotary encoders pulled up to 5V by 22k resistors, don't really know what I was thinking there. Do you think that the 5V on the inputs killed the prop?

    What would be the best way to interface the encoders, I can't find 3.3V ones.
  • SeariderSearider Posts: 290
    edited 2009-09-13 15:35
    the Prop pins tend to be 5v tolerant. and a 22k resistor should limmit the current just fine.

    ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔

    Searider
  • jazzedjazzed Posts: 11,803
    edited 2009-09-13 16:33
    If you post a schematic file it would be easier to help you.

    ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
    --Steve

    Propeller Tools
  • SexieWASDSexieWASD Posts: 41
    edited 2009-09-13 18:19
    I am sorry, but I don't have one. I think that perhaps I may have killed the prop when soldering it, but I'll have to wait for a new one to arrive before I can swap it out. Other than that I am really out of ideas.

    It is getting a stable 3.3V on all of the vdd pins, and all of the vss pins have continuity with the ground plane. I have tried two 5MHz crystals, both from the parallax store.
  • LeonLeon Posts: 7,620
    edited 2009-09-13 19:23
    That PCB looks like it was created with ExpressPCB, so you probably do have a schematic. I doubt if anyone will help you without one!

    Leon

    ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
    Amateur radio callsign: G1HSM
    Suzuki SV1000S motorcycle

    Post Edited (Leon) : 9/13/2009 7:28:16 PM GMT
  • jazzedjazzed Posts: 11,803
    edited 2009-09-13 19:30
    Ok, I assume this is a 4 layer board and you are using the Propeller tool.

    1) Double check to ensure that the Propeller RX pin is connected to the COM device TX pin (Propeller TX should be connected to the COM device RX pin). If there is a short on RX/TX, it can also cause trouble.
    2) If you hit F7 or F10 on the Propeller tool, the RESn pin should drive low briefly from the COM device RES pin. If not the Propeller will not respond properly. An LED attached with anode on RESn and cathode to VSS might blink. Most people can see a 50ms pulse, but I'm not sure how big a pulse the Propeller tool makes.
    3) If your Propeller is receiving > 3.3V on any pin, that pin should have a series protection resistor on it. The effect of driving 5V directly might be a warm device but it should not cause catastrophic failure on the whole chip. Other effects in run time would be input not having effect on your program.

    Don't know what else to add now. Good luck.

    ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
    --Steve

    Propeller Tools
  • SexieWASDSexieWASD Posts: 41
    edited 2009-09-13 20:02
    I could kiss you, but instead I will give you a cookie.

    24080-oatmeal_raisin_cookie.jpg

    It was the Rx Tx lines, a quick swap on my cable and all is good.
    Thank you much.




    And yea I don't have the schematic only the PCB file, I just started with reading datasheets and making traces.
  • jazzedjazzed Posts: 11,803
    edited 2009-09-14 01:04
    Sweet !!! Oatmeal-raisin is my favorite [noparse]:)[/noparse]

    ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
    --Steve

    Propeller Tools
  • Bob Lawrence (VE1RLL)Bob Lawrence (VE1RLL) Posts: 1,720
    edited 2009-09-14 03:16
    @SexieWASD

    Interesting circuit. I need to get some digital pots to play with.

    Good luck with it.


    @jazzed

    Good job with the diagnosis . Actually, you got ripped off. It should have been a least two cookies. lol.gif
  • jazzedjazzed Posts: 11,803
    edited 2009-09-14 16:06
    Maybe I'll get to hear that guitar some day.

    ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
    --Steve

    Propeller Tools
  • SexieWASDSexieWASD Posts: 41
    edited 2009-09-14 21:49
    You will, it's all cut and glued just waiting to test if the circuit sounds ok before the holes are drilled for the encoders, if not I don't know If I will continue with the prop part of it. I don't think that I can really preamp it. Then I just have to learn how to play it. [noparse]:)[/noparse] Either way, prop or not I'll make a video, it's gonna be sweet.

    It's a hollow body strat with a flat top + f-hole.
    Tiger maple neck.
    macassar ebony fret board with an inlay of Cerberus in pearl.
    quilted maple top plate dyed green + yellow.
    redwood burl backplate not dyed.
    all black hardware, with no pick guard.

    I think I have spent near $1500 just for materials, not including shipping, or anything to do with this circuit. The most interesting part is that the entire thing was cut with a home built CNC router table by my brother.

    Here's a few pics of a guitar body he cut just before mine to show off his craftsmanship.

    000_0029.jpg
    000_0030.jpg
  • jazzedjazzed Posts: 11,803
    edited 2009-09-14 22:00
    Nice work. Reminds me of a Les Paul a little. There was another brand with a sunburst and almost exactly that shape ... I forgot the name.

    A friend of mine makes his own guitars ... and plays the heck out of 'em too.
    VoteforJJintheDeanShredderSearch.jpg

    ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
    --Steve

    Propeller Tools
  • propellerheadszpropellerheadsz Posts: 6
    edited 2009-09-14 23:01
    I have a similar problem.

    When i hit F7 in the propeller tool i get communication error:
    No propeller chip found on any serial port.

    I made my own custom programmer and am using the 28-SSOP FT232RL chip and followed the schematics shown in the prop plug pdf for the corresponding pins in the 28-SSOP package.

    I took an oscilloscope and am able to see the bits being sent.
    I opened a hyperterminal and set it to 115200 baud rate and tied both Rx and Tx pins together and verified that what i typed was what was seen back at the terminal.

    I've verified every pin on the board that holds the propeller chip with a multimeter.
    I've downloaded and installed the drivers from the propeller tool - that did not fix the problem.
    I've downloaded and installed the drivers from the FTDI site as well as the Mprog executable.
    I've erased and reprogrammed the FT232RL.

    I'm on windows xp and the drivers are shown to be installed and working properly. I have VCP checked which was why i was able to open the hyperterminal.

    I've also desoldered the propeller and soldered a new one.

    I'm using the schmartmodule dev board.

    any ideas?
  • BradCBradC Posts: 2,601
    edited 2009-09-15 05:14
    SexieWASD said...

    It's a hollow body strat with a flat top + f-hole.
    Tiger maple neck.

    I'd be interested to see what sort of cavity configuration you have to give it a hollow body. Are you using a fixed or floating bridge?

    Who's pickups are you planning on using? Are you planning on burying a piezo in there somewhere to exploit the acoustic properties of the cavity, or is the f-hole just for looks?

    That's a nice looking tele-variant in those photos. Are they Gibson P-90 pickup routes?

    ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
    lt's not particularly silly, is it?
  • BradCBradC Posts: 2,601
    edited 2009-09-15 05:16
    propellerheadsz said...

    I took an oscilloscope and am able to see the bits being sent.

    Are you getting the right shaped pulse on the reset line when you hit the DTR ?

    ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
    lt's not particularly silly, is it?
  • SexieWASDSexieWASD Posts: 41
    edited 2009-09-15 06:54
    Mine has a little different shape to it, but the routing is similar to this:
    bodyb.jpg

    I'm using the following pickups.
    Neck: Dimarzio area 58
    mid: Dimarzio YJM
    Bridge: Dimarzio Steve's Special

    I may switch out the pickup's later as my brother has started winding his own, and I would like a set of true single coils to play with.

    The bridge is a tune-o-matic bridge from graph tech with a piezo pickup in each string saddle.



    I may install an acoustic style piezo at some point just to play with, but the f-hole is mostly for looks.

    I'm not sure what pickups went into the arch top.

    @propellerheadsz, these settings seam to work for me.

    Bits per second 115200
    Data bits 8
    Parity None
    Stop bits 1
    Flow control none
    Receive Bytes 4096
    Transmit Bytes 4096
    Latency Timer 1
    Minimum Read Timeout 0
    Minimum Write Timeout 0
    Serial Enumerator checked

    Post Edited (SexieWASD) : 9/15/2009 7:01:46 AM GMT
  • BradCBradC Posts: 2,601
    edited 2009-09-15 07:28
    SexieWASD said...

    I may switch out the pickup's later as my brother has started winding his own, and I would like a set of true single coils to play with.

    There is nothing like the twang of a nice single coil.
    SexieWASD said...

    The bridge is a tune-o-matic bridge from graph tech with a piezo pickup in each string saddle.

    I've never heard piezo's in a Strat. I look forward to hearing what it sounds like!
    SexieWASD said...

    I may install an acoustic style piezo at some point just to play with, but the f-hole is mostly for looks.

    There's not a lot of meat in the centre of the guitar by the time you route out the pickups and trem springs, so I think you may suffer a lack of sustain. On the flip side, if you make sure the top is nicely secured and braced, both sides of it should sing nicely and with different resonances. If that makes it back up to the bridge via the trem posts then you should get some interesting harmonic resonance through your saddle pickups. It should howl like a banshee in front of a good amp with lots of gain. Make sure your pickups are wax or epoxy dipped to keep the pickup feedback away and let the body resonate.

    All in all it sounds like a really interesting machine. Now you just need to add some small linear drives and make it self-tune [noparse]:)[/noparse]

    ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
    lt's not particularly silly, is it?
  • jazzedjazzed Posts: 11,803
    edited 2009-09-15 14:46
    A self tuning guitar ? Manna from heaven [noparse]:)[/noparse]

    ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
    --Steve

    Propeller Tools
  • propellerheadszpropellerheadsz Posts: 6
    edited 2009-09-15 17:52
    I checked the voltage drop on the resn bar pin and it drops from 3.3V to about 2.9V which is probably why the propeller is not able to be identified.

    I think i need a different npn pull down transistor...
    does anyone have any recommendations as a specific model as it is not specified in the documentation?
  • BradCBradC Posts: 2,601
    edited 2009-09-16 00:19
    propellerheadsz said...
    I checked the voltage drop on the resn bar pin and it drops from 3.3V to about 2.9V which is probably why the propeller is not able to be identified.

    How did you check the pulldown? The pulse is only about 10-15mS so you need to have the CRO set up right to measure it properly. It has a sharp falling edge, but the rise tends to float up a bit gently.

    ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
    lt's not particularly silly, is it?
  • propellerheadszpropellerheadsz Posts: 6
    edited 2009-09-17 18:18
    I only checked it with a multimeter...i'll put a scope to it to make sure.

    also, CRO?
  • BradCBradC Posts: 2,601
    edited 2009-09-18 00:38
    propellerheadsz said...
    I only checked it with a multimeter...i'll put a scope to it to make sure.

    also, CRO?

    Cathode Ray Oscilloscope.

    You won't get any reasonable results on the reset pin without a CRO. The pulse is so short your DMM will see it as a glitch at best.

    If you have dual trace, you should see the reset pin pulse low and about 100ms later you should see the first byte of the handshake come from the prop. (give or take 10-15ms either way)

    ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
    lt's not particularly silly, is it?
  • propellerheadszpropellerheadsz Posts: 6
    edited 2009-09-23 01:11
    propeller version 1 found.

    It turns out that my recieve pin was not properly connected to pin 37 of the propeller chip. I resoldered and soldered still could not make a connection when i buzzed it with a multimeter - so I "hardwired" it to pin 9 of the J8 Header.

    I am using the schmartmodule. Not sure if there is a problem with all schmart boards as none of you seem to be using this dev board.

    hope this helps someone with the same board. Here is a link to the board i'm using:

    http://www.schmartboard.com/index.asp?page=products_populated&id=205
    but i actually got it at defcon so it looks really like this:
    http://blog.schmartboard.com/.a/6a00e54ed57a3b88330115723c6c09970b-pi
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