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Cheap PropPlug replacement - USB-TTL converter US$4.60 and a modification - Page 2 — Parallax Forums

Cheap PropPlug replacement - USB-TTL converter US$4.60 and a modification

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Comments

  • Cluso99Cluso99 Posts: 18,069
    edited 2012-07-09 18:11
    No. Keep the same cap due to some timing issues with the prop and proptool.

    IMHO the 10K series resistors in TX and RX are a bit high. I would prefer 1K, but the PropPlug uses 150R IIRC.

    Any general purpose NPN transistor can be used such as 2N2222, etc.
  • purplemonkeypurplemonkey Posts: 89
    edited 2012-07-27 11:03
    OK done it soldered a jump lead to rts on the side of the plug to the middle part of that circuit you put up the diagram for and prop tool still can't find it. Does the tx on the plug go to the rx on the chip and the rx on the plug got the tx on the chip? Also Does vss and boen both just go to ground or do they touch resn? I think it maybe the memory chip that's the problem should prop tool still recognise the chip without memory installed? And lastly when plugging it in to computer should battery be attached or not?
  • purplemonkeypurplemonkey Posts: 89
    edited 2012-07-27 11:05
    Oh and also presumably I don't need any extra drivers or software just the prop tool on windows 7
  • purplemonkeypurplemonkey Posts: 89
    edited 2012-07-27 11:10
    Sorry one more is the flat side or the transistor in the diagram facing the capacitor or not? Sorry newbie question I know
  • purplemonkeypurplemonkey Posts: 89
    edited 2012-07-27 11:40
    Just thought as I'm using existing connections for rxd and txd and ground I don't need those 10k resistors on any of them except the reset to ground is that right or do I still need to put them in? Just as I would assume as I'm using existing connections for those three the plug would have resistors in place for those anyway?
  • Duane C. JohnsonDuane C. Johnson Posts: 955
    edited 2012-07-27 14:44
    Reset is pulled up to VDD through a 10K resister.
    If pulled low the Prop won't do anything.

    BOEn is permanently connected to VSS unless you have extra under voltage detection circuitry.

    Duane J
  • purplemonkeypurplemonkey Posts: 89
    edited 2012-07-28 05:32
    Thanks but what about tx and rx presumably they have resistors built onto chip already or do I need external resistors for those too?
  • purplemonkeypurplemonkey Posts: 89
    edited 2012-07-28 05:34
    What do you think christoph?
  • purplemonkeypurplemonkey Posts: 89
    edited 2012-07-28 06:39
    photo.JPG
    photo1.JPG
    photo2.JPG


    this is what i've got am i missing something? i haven't cut any tracks????
    640 x 480 - 128K
    640 x 480 - 142K
    640 x 480 - 132K
  • Dr_AculaDr_Acula Posts: 5,484
    edited 2012-07-28 06:50
    The prop needs the reset line as well. I don't know anything much about these USB to TTL converters, but I do know you need to reset the propeller at a precise time. I tend to start with this schematic http://elmicro.com/files/parallax/propdemod_schematic.pdf

    and presumably your converter replaces the FT232. Do you get a DTR output?

    Is the yellow wire the DTR?
  • Christoph_HChristoph_H Posts: 31
    edited 2012-07-28 08:47
    this is what i've got am i missing something?
    It looks alright.
    The yellow wire you use for reset is RTS. Make sure the Propeller Tool is enabled to use it. (Edit -> Preferences -> Operation -> Propeller Reset Signal - select RTS or DTR & RTS)
    photo1.JPG
    The right red wire which is connected via resistor to the dongles RXD pin has to be connected to propeller pin 40 ("P31"). The left one which is connected via resistor to the dongles TXD pin has to be connected to propeller pin 39 ("P30").
    The orange wire coming from the collector of your transistor has to be connected to pin 11 ("RESn") and, as Duane wrote, pin 10 ("BOEn") must be connected to ground. Please double-check the connections.

    If it still isn't working, post a picture of your complete breadboard so we can also see the propeller chip and tell us which type of transistor you are using.
  • purplemonkeypurplemonkey Posts: 89
    edited 2012-07-29 03:05
    Thanks I'll rewire it all and try again. Do I need any other software for the bst tool or extra drivers etc. it's already installed silicon uart drivers. Also does the bst tool default to rst as can't seem to find a preference for changing it in bst?Lastly do I need battery connected when connecting to mac?Also does the Rom need to be connected for bst to see prop chip?
  • purplemonkeypurplemonkey Posts: 89
    edited 2012-07-29 03:31
    Oh and I'm using a 2n3904 transistor
  • purplemonkeypurplemonkey Posts: 89
    edited 2012-07-29 04:01
    Oh and I'm using a 2n3904 transistor
  • purplemonkeypurplemonkey Posts: 89
    edited 2012-07-29 08:59
    Thanks it's working now it was just because I wasn't logged on as admin on pc so prop tool wasn't working right bst still doesn't work though.

    Is it possible to broadcast a signal at a higher frequency than 128mhz with the prop chip?

    Secondly is it possible to have an input for microphone so that it broadcasts voice on the selected frequency?
  • LoopyBytelooseLoopyByteloose Posts: 12,537
    edited 2012-07-29 09:02
    128mhz? You would have to overclock the Propeller to get your carrier frequency from it. That would mean a higher crystal, a heck of a lot more heat (maybe glue on a heat sink), and a serious risk of sudden instability.
  • LeonLeon Posts: 7,620
    edited 2012-07-29 10:01
    128mhz would be OK, but not much use. 128 MHz is another matter!
  • CircuitsoftCircuitsoft Posts: 1,166
    edited 2012-07-30 11:19
    milliHerz, MegaHerz, same difference...

    /me runs and hides
  • purplemonkeypurplemonkey Posts: 89
    edited 2012-08-05 10:26
    Ok it's working fine except I keep getting write to com 3 failed but only when uploading the fm transmitter spin with wav file from this board. Seems to be timing out?? Would it be better to connect reset to Dst rather than rst? Or is it a driver issue?? Any ideas???
  • Cluso99Cluso99 Posts: 18,069
    edited 2012-08-05 16:06
    You mean DTR rather than RST (data terminal ready vs request to send). No difference likely.

    Have you tried the latest (last week or so) PropTool? It has some timing changes that may??? help.

    If not, you could try changing the R & C values in the transistor reset circuit. R is easiest. I am not quite sure of the prop timing to know if this might help or not.
  • purplemonkeypurplemonkey Posts: 89
    edited 2012-08-09 08:25
    Which version of the silicon uart driver should I be using by the way?
  • Cluso99Cluso99 Posts: 18,069
    edited 2012-08-09 19:52
    I don't recall if I used the one that came with the board or let Windows find one automatically. Most likely I would have let windows try and locate a driver from the internet.

    You have problems with downloading the wav file. I presume this is downloaded by other than PropTool? i.e. not part of the actual compiled cpde download? If so, I wonder if there is a problem with whatever code/object is doing the download. Maybe the wav file is too big. Maybe a buffer overrun. Hard to say without more info and understanding what the software is doing.
  • purplemonkeypurplemonkey Posts: 89
    edited 2012-08-14 10:42
    Do I have to cut the trace from the reset line on the dongle? Would this maybe the problem?
  • Christoph_HChristoph_H Posts: 31
    edited 2012-08-15 01:07
    Do I have to cut the trace from the reset line on the dongle
    No. If you still have everything wired up like in the pictures in your post #40 it should be working.

    Describe exactly what you are doing when you get "write to com 3 failed". That's the easiest way to get help and was already suggested by Cluso99.
  • purplemonkeypurplemonkey Posts: 89
    edited 2012-08-15 10:48
    No. If you still have everything wired up like in the pictures in your post #40 it should be working.

    Describe exactly what you are doing when you get "write to com 3 failed". That's the easiest way to get help and was already suggested by Cluso99.

    I'm literally just connecting battery to breadboard then plugging in USB thingy then starting prop tool and then I checked it could find prop tool and it did identify one prop chip I then opened the spin file which is in the same folder as the WAV file and the went compile current eeprom and it starts to load ram and then hangs for a little bit and then says write on com 3 failed. All other program's that I compile that don't have external WAV files say they have worked but the prop doesn't seem to do what it's supposed to. Just goes sssh-break-sssh on the radio and then dies after a few seconds and it's not very powerful it needs to be directly on the radio. Also it doesn't work at all when I try and use BST tool on mac, it won't even see the chip


    Code is here.

    http://forums.parallax.com/attachment.php?attachmentid=94811


    As an attachment
  • Christoph_HChristoph_H Posts: 31
    edited 2012-08-16 09:36
    I can confirm loading the program in the zip file doesn't work on my machine/board either. That's Windows XP (x86) with Propeller Tool 1.3.2 and CP210x driver 6.5.3; the error message is "Write failure on COMxx.". It looks like this is the behaviour described in the thread USB download cables. You could follow the suggestions by Ariba in that thread and use an older version of the Propeller Tool.

    Another possibility (worked for me) is propeller-load from the Propeller GCC / Simple IDE project. To use it install SimpleIDE and execute
    propeller-load -p COM3 -D reset=RTS -r 2m_fm_modulation1.binary
    
    This runs your program; to also write to EEPROM add "-e" on the command line. To create 2m_fm_modulation1.binary press F8 in the Propeller Tool and choose "Save Binary File".
  • purplemonkeypurplemonkey Posts: 89
    edited 2012-08-17 04:50
    I can confirm loading the program in the zip file doesn't work on my machine/board either. That's Windows XP (x86) with Propeller Tool 1.3.2 and CP210x driver 6.5.3; the error message is "Write failure on COMxx.". It looks like this is the behaviour described in the thread USB download cables. You could follow the suggestions by Ariba in that thread and use an older version of the Propeller Tool.

    Another possibility (worked for me) is propeller-load from the Propeller GCC / Simple IDE project. To use it install SimpleIDE and execute
    propeller-load -p COM3 -D reset=RTS -r 2m_fm_modulation1.binary
    
    This runs your program; to also write to EEPROM add "-e" on the command line. To create 2m_fm_modulation1.binary press F8 in the Propeller Tool and choose "Save Binary File".

    That's great thanks at least I know now it's not just me, where do I get simple IDE from?
  • purplemonkeypurplemonkey Posts: 89
    edited 2012-08-17 05:05
    did you check it on a radio? also i've read that when testing some people have a 100 ohm resistor instaed of the antenna. Am i right in thinking the 100 ohm resistor would go from pin 6 to ground?
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