Jump to content


  • Content count

  • Joined

  • Last visited

  • Days Won


chicken last won the day on January 10

chicken had the most liked content!

1 Follower

About chicken

  • Rank
    Level 4

Contact Methods

  • Website URL

Profile Information

  • Gender
    Not Telling
  • Location
    Redmond, WA
  • Github
  1. Shouldn’t there be a special badge on 43oh for earning 430 reputation points? Well, congrats to my dear friend @Fmilburn for having crossed that line of 43oh awesomeness
  2. [POTM] dAISy - A Simple AIS Receiver

    Hi Fonsin, Glad to hear that you successfully upgraded your dAISy USB. As for the NMEA-0183 adapter: I didn't plan to build new ones as I think the 2+ is the more robust solution. But there were recently a number of requests from current owners of the dAISy USB, so I will probably spin a small batch in the next few months. It seems like the NMEA-0183 listeners are not too picky. Some (e.g. Garmin) even use just one data wire, which may directly work with the UART output on TX. Though input protection may be an issue. On my adapter I use the TI UA9638, which is also available as DIP package (UA9638CP) http://www.ti.com/product/UA9638 This IC is very easy to use. Just connect 5V, GND and TX, and you get a RS-422, i.e. NMEA-0183 compliant, differential output. And maybe add a 0.1uF and/or 1uf capacitor across the power pins if you want to get fancy. The downside of the UA9638 is, that it's relatively power hungry (50mA) compared to the rest of dAISy USB. It is responsible for 75% of the increased current consumption of the dAISy 2+. There are other RS-422 drivers which seem to be lower power, like for example the ST485 or MAX485. But I haven't used any of these. This document goes into great detail about the electrical characteristics of NMEA-0183: http://www.actisense.com/wp-content/uploads/2017/07/NMEA-0183-Information-sheet-issue-4-1-1.pdf Best Regards, Adrian PS: As for logic gates, the 74HC00 could be a good alternative for the transistor. It depends a bit on the required current, but the NMEA-0183 spec says 2mA per listener, which a logic gate should be able to deliver. Another option is to use 74HC04 to create a true differential signal (1 inverter for one line, and 2 inverters in series on the other line).
  3. MSP430FR2433 LCD16x2

    I don't have a MSP430FR2433, but a few items come to mind: 1) Does the LCD display support 3.3V input? Most Arduinos are running at 5V, but the MSP430 family is 3.3V. 2) Did you check if just wiggling a pin works? E.g. by turning on an LED or measuring with a multimeter? If that doesn't work, some additional GPIO configuration may be needed. 3) If you have a logic analyzer or oscilloscope, check if the timing of the pin wiggles is as expected. Your code seems to assume, that the clock is running at 750KHz. I don't know if that's the speed at which the FR2433 starts up without any further configuration.
  4. [POTM] dAISy - A Simple AIS Receiver

    This is the relevant line in radio_config.h: #define RF_GPIO_PIN_CFG 0x13, 0x1A, 0x00, 0x11, 0x14, 0x1B, 0x00, 0x00 ..which in the M4463 branch looks like this: #define RF_GPIO_PIN_CFG 0x13, 0x11, 0x00, 0x21, 0x20, 0x14, 0x00, 0x00 I have a few bare boards of the booster pack laying around. Happy to solder them up if there's interest.
  5. [POTM] dAISy - A Simple AIS Receiver

    Hi Sven, I think the MSP430 side is ok. It looks like your setup is able to configure the radio, and something is received. Sync indicates, that the packet handler ISR found preamble and start flag. Did you already try the regular branch? The 4463 branch is quite stale, and it looks like I did a few changes to radio configuration and packet handler on master after the branch. Regards, Adrian
  6. [POTM] dAISy - A Simple AIS Receiver

    Yes, message type 24 is supported. dAISy itself is not really aware of the AIS message contents. It will forward all valid AIS messages it receives. You may see fewer Class B messages than expected because: Class B transponders are much weaker than Class A, and therefore more prone to noise interference. Especially for long messages like static data. Class B messages are typically sent less frequently than Class A
  7. [POTM] dAISy - A Simple AIS Receiver

    Happy to hear that, and thank you for the review on Tindie! I had to lookup how a Jon boat looks like With that low height, I'm surprised of the 7 miles range.
  8. Here's something new in the "I would like to play with that" category: A pico-projector in the form factor of a BeagleBone Black cape. At $99, the price isn't too bad either. http://www.ti.com/tool/dlpdlcr2000evm#0
  9. [POTM] dAISy - A Simple AIS Receiver

    @nazmibojan your radio IC may be toast by now, so you may have to replace it. @longjohn119 thank you for the detailed report. My own knowledge about antennas is very basic. It's definitely much noisier around here in suburban Seattle. Also always interested how the receivers compare to SDRs, as basically it's a very specialized SDR. For a fairer comparison, you could try to add a bandpass filter in front of the SDRs. My 1-channel dAISy has a discrete LC filter built from SMT components, and it holds up surprisingly well to the SAW filter used on other models. In real world tests the advantage of the SAW was maybe 10% more messages. An external filtered preamp can help. I observed better range when adding this one in front of the HAT: https://store.uputronics.com/index.php?route=product/product&product_id=93 Adding a preamp on-board is still on my to-do list. I did early experiments which resulted in worse reception. However by now I know that the small dAISy is limited by noise from the USB side. I may give it a try with the HAT, which despite the integrated splitter performs as good as the single-channel dAISy, i.e. the design likely has a lower noise floor.
  10. [POTM] dAISy - A Simple AIS Receiver

    I usually have the check for the CCA condition turned off as well. It only did make sense for single-channel receivers where RSSI level can be used for more intelligent channel hopping (didn't make much of a difference). I still suspect noise to be your main issue.
  11. [POTM] dAISy - A Simple AIS Receiver

    Excessive power would be my guess if the receiver doesn't work anymore. The radio IC is only rated to an absolute max of 10 dBm, equivalent to 10mW. You can somewhat protect the radio with two parallel PIN diodes from RF to ground. One with cathode to GND and the other the opposite way. This clamps the signal to a maximum of less than +/- 0.7V, the equivalent of 10dBm. Though not sure how long that would help when directly connecting the receiver to an AIS transponder.
  12. [POTM] dAISy - A Simple AIS Receiver

    Hi Rian, Is this repeatable? I.e., when you reboot dAISy it works again for a few minutes?
  13. [POTM] dAISy - A Simple AIS Receiver

    Regarding your range problem: I program the firmware on my HATs with the debugger on the MSP430F5529 launchpad. If I don't power cycle (unplug and reconnect USB) after programming and before testing, I see elevated noise levels. I don't know the exact reason, but suspect that the JTAG traffic on USB introduces noise. Maybe there's a similar issue with the Discovery boards.
  14. [POTM] dAISy - A Simple AIS Receiver

    Hmm, it's a while since I looked at it in detail. Channel spacing is 50KHz. If I remember correctly, bandpass was set to 20 or 15KHz. I stay away from building a transponder as there's a real risk of disrupting AIS traffic if done wrong. But if you want to go down that avenue, check out this project: https://github.com/peterantypas/ais_transponder
  15. [POTM] dAISy - A Simple AIS Receiver

    I apologize for the slow response. Besides configuration, severely limited range can be a noise issue. You may introduce noise to the radios with the wires connecting over to the STM32. The radio_config.h for the Si4362 should be a good starting point as the EzRadioPRO chips are compatible. You can generate the radio_config files for the Si4467 with the WDS tool from Silabs: https://www.silabs.com/products/development-tools/software/wireless-development-suite Seems like they changed the file format since the last time I used it. The attached project file can be loaded with the latest version of WDS. I also attached a radio_config.h for the Si4467 that I created with this project file. I haven't tested the results though. WDS3211_si4362_revb1_direct_rx.xml radio_config_Si4467.h