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Everything posted by geodave

  1. I am trying to do exactly what spirilis describes in the hypothetical remote sensing application on his wiki for the nrf24L01+ library: "A typical application of the nRF24L01+ which takes full advantage of the MSP430's touted low-power modes is remote sensing with periodic wakeup involving an MSP430 circuit attached to sensors in a remote location. An MSP430 using either the VLO or LFXT1 driving ACLK to wake up the device periodically will switch on the nRF24, take sensor measurements and once the nRF24 is ready (5ms Standby-I wakeup time has elapsed), transmit those to a base station, fol
  2. I am embarrassed to admit the my CE and CSN lines were switched. I checked it at least 10 times over the course of two weeks. I guess in life sometime it takes 11 tries. Code works as is! Hopefully this post will be useful to someone. No packet loss. Haven't tested the distance yet. Wiring for the Pi is as follows: radio 7 (miso) to gpio9/bcm21 radio 6 (mosi) to gpio10/bcm19 radio 5 (sck) to gpio11/bcm23 radio 4 (csn) to gpio8/bcm24 radio 3 (ce) to gpio25/bcm22 radio 2 (3.3v) to 3.3v radio 1 (gnd) to gnd Get it right or pay the price!
  3. Sadly I have not gotten it working yet but it is good to know someone has. It just means I am doing something wrong. When I call printDetails() it doesn't show the address or setting that I have specified. I thought it might be the wiring to the pi but I have checked them about 10 times and they are right. Maybe I didn't install and configure the library correctly. Not sure. My two MSP430's talk find across the house as well. Would you mind posting you MSP430 and Raspberry Pi code? I will load it up and see if I can get it to work and see if it also has packet issues.
  4. I couldn't find an example of someone using the Raspberry Pi as a receiving hub for sensor nodes that use the spirilis nRF24L01+ library and a MSP430G2553. I thought I would give it a shot since I think this would be beneficial to the community. I found a C library for the Raspberry Pi and nRF24L01+: https://github.com/stanleyseow/RF24. Class reference is here: http://maniacbug.github.io/RF24/classRF24.html There is also a newer python library but I haven
  5. Project update: I have been casually testing the setup for the past couple weeks with mixed results. Most of the testing includes a screaming infant on my shoulder. You can imagine why this project is moving so slowly. The main issues with the current setup seems to be the range. It will transmits okay the first times but the signal seems to get weaker with subsequent transmissions. I have purchased a NRF24L01+PA+LNA module to put on the receiver end. I am hoping this will get me a bit more distance so it is more usable. In the meantime I am going to work on the charting interface.
  6. Yep...I added a 100uF 10v capacitor to the Vin and was able to get another 25 feet of range with the receiver in the window facing the garden. I also tested in the house and got about 40 to 50-feet through 3 walls. Is this range consistent with what you are getting on these wireless modules with the trace antenna?
  7. Source is one AA rechargeable Ni-CD 800mAH. Okay so you are thinking if I put the larger capacitance on the Vin side it will stabilize the input and thus provide a stable output?
  8. I can't believe it has almost been a month since the last post...sorry! I have the fortune of visiting former soviet republics a couple times of year for work so I have been out of town. So I did install the new 10uH inductor with the two 10uF ceramic capacitors and it didn't work. Switched the Vin and Vout capacitors for cheap 22uF 16v electrolytic and it works sporadically. I removed the 22uF from the Vout and replaced it with a 68uF 16v cheap electrolytic capacitors and I am getting better performance. I currently have the transmitter in the garden and the receiver in a window about 3
  9. Thanks again @@spirilis. Sounds reasonable. I am thinking of ordering these inductors: http://www.mouser.com/ProductDetail/Bourns/78F4R7J-RC/?qs=sGAEpiMZZMsg%252by3WlYCkU1wbcydNIDvKD70RmuEuJkg%3d http://www.mouser.com/ProductDetail/Fastron/SMCC-N-100J-01/?qs=sGAEpiMZZMsg%252by3WlYCkU8BLlVcluYKE51pm1lHTf0E%3d These have higher current ratings and a resonable price. What do you think?
  10. The capacitors are ceramic 10uF 16v. I replaced them with 22uF 25v aluminum electrolytic to see if that would help and it didn't. Then I tried adding a 16uH inductor...no luck. I did hook up a 3.3v power supply to the battery terminals and it does work when you apply 3.3v. I tried using two 1.2v AAA's did not work. Grrrr. It seems like it wants more voltage. Ready for this one? So I decide to set rf_speed_power = RF24_SPEED_MIN | RF24_POWER_MIN to see if it was a power issue because I think this code means slower transmission speeds and less power consumption but more range as I understand
  11. Thanks for the response @@spirilis! I stuck a 22uF 25v capacitor on C4 and that didn't fix it. The inductor I am using is 10uh and I am not sure what it is rated to since it is the salvaged part from the light. It is a basic axial through hole and looking online those seems to range between 180 and 265ish mA. I can see how this might be causing the issue. I just started getting into soldering surface-mounted components but I would like to start using those more. My current PCB design uses through hole axial inductors so I might try to stick with those on these boards. I appreci
  12. I have a 10uf 16v ceramic capacitor on the DC-DC boosters VOUT. I also have a 0.1uf capcitor tied to the 3.3v line for the photoresistor circuit. I don't have anything for the nRF24 module but I will add one tonight and see if that helps. You can view the schematic on the first post. Thanks for the tip!
  13. I did populate the entire PCB tonight so I could stick it outside and test it with the Raspberry Pi. Only one problem...it doesn't work. Everything on the PCB is wired correctly because it works when I apply 3.3v directly to the MSP430G2553 DVCC and DVSS pins. I know I am getting 3.3v to the chip from the DC-DC boost converter because I can read it on my multimeter. I think this leaves me with a current issue. The TPS61097-33 DC-DC booster can source up to 100mA depending on the voltage. Apparently that is not enough to supply the circuit and/or code. http://www.ti.com/product/tps61097-33
  14. Thanks for the reply! Correct, the code works beautifully when you comment out the start/end offending code block. I can view the outgoing char buf through CCS and it looks normal. That is why this is so frustrating. It makes me sad you also think it is strange. I was hoping for an obvious mistake. I don't believe s = r_rx_peek_payload_size is the issue. Before I wrote the current rx code I was using Ike's example receiver code and I had the same issue with the thermister code block. Ike's code doesn't use r_rx_peek_payload_size to determine the size of the message payload
  15. @@spirilis maybe you can help me sort this out. I am still having issues with my thermister code. The math is correct and does show the current temp in the outgoing char buffer. I do believe it is transmitting because I am using USCI_B on the launchpad and I can see the 1.6 led flicker when the packet is sent. However, my receiver code isn't picking it up. When I comment out the offending math and just pass the raw adc the receiver picks it up 100%. I am using Opossum's printf library on the receiver side to print to UART. I have also made some changes so the packet size is dynamic.
  16. I still haven't figured out what is wrong but I do think it has something to do with the floating point math. I do believe the transmitter is sending a packet. Perhaps the floating point path calculation is causing a timing issue with the wireless transceiver. Anyone else got any ideas on that? I know the kelvin equation is correct because I used it in another project on the MSP430. The good news is that I have a basic version of my receiver code working. I am able to print my sensor data (the working sensors) in delimited format and chart if using the python script, Apache serv
  17. Thanks @@spirilis! These code adjustments did make the the code better. I was having issues with the data being loaded into the middle of the char buf array. For example, the first int in the char array would populate buf[6] on the rx side instead of buf[0]. I assume changing the clock setting resolved this issue. I didn't read your config file completely and totally missed that part of the configuration! :?
  18. Baby boy was born and I have been sick for a week and a half so that has slowed my progress. I did play with the bypass switch on the DC booster and came to the conclusion that I need to reduce the total resistance over R2 and R3 to 340kohms down from 400kohms. This seems to work well, though, I haven't been able to determine the exact switching voltage because the datasheet is confusing in that regard. I think it is turning on the voltage bypass switch at between 1.1 and 1.2v. I have been reading about character arrays and sprintf and trying to come up with a good way to pass t
  19. Thanks for the comments @yyrkoon. I haven't really decided on the timing yet. You are probably correct that the sampling rate it too high. My plan is trial and error once I get a working version going. There are lots of concerns I have with the crude soil sensor. For example, resistance changes with temperature but I am not sure to what extent. I have found some equations that take into account soil temp, resistance, and soil type to determine the soil moisture level. You can adjust the coefficients in that equation based on the crop type to get an idea moisture value. See http://w
  20. Thanks @roadrunner84. Yea, that was the intention of JP4. I probably should have tested programming the chip outside the launchpad before I added the porgramming pins (it was a last minute thing and I have never done it before). Thanks for the heads up! I will revisit the reset switch based upon your comments and repost the schematic when I finish.
  21. Thanks for the feedback! Maybe...it would required a way to step down the volatge 50.v to 3.6v or less (maybe using some diodes?)...or you could use an Arduino. What would be the advantage to two batteries? I only plan to turn this on once or two times an hour if that so I don't expect a large power draw.
  22. I will play with the bypass resistors tonight after work. I like the pot idea. A couple friends of mine have had a different model (same brand) of these controllers in their yards for about a year and they are still going strong. I am not too concerned about the weather proofing as they are desgined to be outside. I am a little concerned about the mechanical reset switch. I don't think I really need the switch...it can just be handy to have.
  23. Voltage level was equal to the battery which seems to indicate that it was enabled. I suppose the button is a good point. Not sure how much condensation to expect. It is weatherproofed to a certain extent. Do you think it would be best to just remove the reset?
  24. Thanks! Bypass feature turns off the voltage booster when battery power drops below a certain voltage (threshold determined by the resistors). Presumably this would save some power though I am not sure this will be an issue as I only plan to log data every half hour to an hour...so it won't use much power anyway.
  25. Greetings! I am new to the forum and this is my first solo microcontroller project. Please be kind to me as I am a Geographer and by no means a programmer or electrical engineer. Stupid questions should be expected. The basic idea of this project is to convert a $3-4 solar light found at Lowes and Home Depot hardware store (here in the US) into a wireless remote sensor node. The node will utilize an MSP430G2553 MCU and a nRF24L01+(w/ spirilis library) wireless module to send light intensity (photoresitor that came with solar driveway light), soil moisture (design from http://gardenbo
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