spirilis 1,265 Posted February 12, 2013 Share Posted February 12, 2013 Here's my variation of a wireless sensor node... this was inspired by a need to monitor temperatures throughout the house; I have 6 of these boards from OSHpark I just got today! http://spirilis.net/junk/msp430/tempbug.jpg Bulk of the package is the 2xAA battery pack, and I have one of my 10-pin nRF24 breakout boards with my new 10-to-8 adapter board from oshpark. Nice & compact! Works off the G2452, I shortsightedly only offered 2 GPIO pins to mess with, P1.0 and P1.1 (the rest are used by the nRF24 or not broken out). Has pads for the PW20 version of the G2452 but since P2.0-P2.5 aren't used at all, a PW14 version works fine (got a 14-pin sample from TI on there). Has one yellow LED, 3 pins for GND/TEST/RESET for programming, and the P1.0/P1.1 pins you see at the bottom. t0mpr1c3 and roadrunner84 2 Quote Link to post Share on other sites
t0mpr1c3 91 Posted February 12, 2013 Author Share Posted February 12, 2013 If you have posted the schematic somewhere, I'd like to take a look please. Any particular reason you went with the G2452? Making good use of your adapter, I see! Quote Link to post Share on other sites
spirilis 1,265 Posted February 12, 2013 Share Posted February 12, 2013 Here's my schematic: DipTrace Schematic - Wireless_ADCTempSender_draft1.pdf OSHpark gerbers: Wireless_TempSender_nRF24.zip I started using the G2452 with my grill monitor, it seemed like at the time I was going to make it a solution based on a LaunchPad with the G2553 being the base station (for its UART) and the G2452 being in the external unit; shortly after I decided to use the SMD version of the G2452 instead, but my decision was made. IMO it's a perfect chip for external nodes like this that don't need a UART; and the USI SPI implementation can do 16-bit, which I have found improves throughput (examined with the logic analyzer) to the nRF24L01+ module. Probably not a big deal or consideration though. That and it's slightly cheaper than the G2553. I ended up sampling some 14-pin TSSOP and bought like 5 of the 20-pin TSSOP versions recently. I like both of them (G2553 and G2452). So in conclusion, I used the G2452 because I felt like it! t0mpr1c3 1 Quote Link to post Share on other sites
t0mpr1c3 91 Posted February 12, 2013 Author Share Posted February 12, 2013 Thanks for the files! I suppose for me the only real advantage of using the G2553 is that the master station (which might need UART) can use the same board. Quote Link to post Share on other sites
t0mpr1c3 91 Posted November 21, 2013 Author Share Posted November 21, 2013 I finally got around to revising this board. I ditched the mini USB and regulator in favour of 2xAA. I also figured out how to measure the battery voltage without using a voltage divider and broke out the pin I was using for that as an analogue input with RC filter. A few other small changes including using a through hole tactile switch. After nearly a year I'm about ready to send off for the boards. Thanks everyone for your help! Quote Link to post Share on other sites
t0mpr1c3 91 Posted December 3, 2013 Author Share Posted December 3, 2013 What it's going to look like. Hopefully I'll get them from Elecrow in time to do something for the current project contest! bluehash 1 Quote Link to post Share on other sites
voodoofish 35 Posted December 7, 2013 Share Posted December 7, 2013 I've been thinking of designing a board as well for use with the nrf24l's since seeing Spiriliis post and code. Something similar in size and compact similar to yours. Wondered if you had looked at different crystal options. Just wondering as I was able to source some smaller rectangular ones and mounted them closer to the xtal pins which saved a lot of space compared to the barrel type. I also opted to use the internal caps vs the external option to save space(and soldering headaches that could be involved). Had you looked into using lipo cells? I've been using a small setup that allows for usb charging, of the small lipo's plus vreg which is very handy for charging the cell as needed. Quote Link to post Share on other sites
t0mpr1c3 91 Posted December 7, 2013 Author Share Posted December 7, 2013 There are certainly smaller options than the 3x8 watch crystal I specified, but I happen to have a bag of them and they are cheap. Lipo + USB charging sounds like an excellent option. I might look into that if I get round to version 2. Can you point me to your design, I couldn't find it from a quick poke around in your gits. Quote Link to post Share on other sites
t0mpr1c3 91 Posted December 23, 2013 Author Share Posted December 23, 2013 The PCBs arrived from Elecrow a couple of days ago and I populated the first one. This may be the first time I have successfully soldered a TSSOP. This one is configured with a 3-pin SIP header for a 1-wire sensor instead of a 3.5mm jack socket. The 4 pin header will be used for output, so I left off R6 and C6 and substituted 0 ohms for R7. I went backwards and forwards over the orientation of the NRF24L01+ header and eventually decided to leave it so that with a 2x4 female pin header the radio module would extend back over the board. This allows for greater compactness but renders the push button inaccessible. One way around that is to use a right angle female header. Another way is to solder the push button on the back (an advantage of using a through hole button) so long as the battery pack pack is not in the way. Tonight I will try to get a "hello world" blink light demo going to test the microcontroller, and if all is well I will attempt radio communication - at long last! Rickta59 and dubnet 2 Quote Link to post Share on other sites
t0mpr1c3 91 Posted December 24, 2013 Author Share Posted December 24, 2013 Soldered up a second board this evening, and fired up a simple script to blink the LEDs. I was able to program both boards, although on one the green LED wouldn't blink so evidently pin P2.3 needs resoldering. First impressions are that the LEDs I'm using are very bright, so the 330 ohm resistors can probably go up to 1K or something. Quote Link to post Share on other sites
bluehash 1,581 Posted December 24, 2013 Share Posted December 24, 2013 Looking great! Is that a lightning bolt? Quote Link to post Share on other sites
t0mpr1c3 91 Posted December 24, 2013 Author Share Posted December 24, 2013 It's a quality seal indicating that all the electricity in the device has been zapped out and the magic smoke pre-released to ensure 100% safety on site. bluehash 1 Quote Link to post Share on other sites
gsgill112 0 Posted December 25, 2013 Share Posted December 25, 2013 Hi t0mpr1c3 , I was working on the same project for a couple of months now, I have done the initial prototyping and testing , but have to design a proper PCB for this Node. I have posted my work here and am working towards creating design files. https://plus.google.com/communities/109693409208144097271 I have used TI's MSP430G2553 DIP So that any time we want we can change the IC. I was able to make one node within 5$ with Ti's Samples Program , and my estimate would be arround 7-8$ for the finished product. I hope we could colaborate towards a Software stack easy to use.(Rt NOW i am using Energia with the nRF Lib) Quote Link to post Share on other sites
t0mpr1c3 91 Posted December 25, 2013 Author Share Posted December 25, 2013 @Gurinder Looks like you are making progress. It hadn't occurred to me to use Energia but that might prove be an easy way to interface some of the sensors. So far I have been looking at the examples in the msprf24 library. I adapted the code very slightly for compilation with msp430-gcc and made some baby steps. I now have 2 launchpads with G2553's on talking to each other from opposite ends of the house and happily blinking their LEDs. I am very pleased with the Spirillis NRF24L01 boosterpacks that I got in the group buy. Next I will try sending a bit of real data, perhaps from a DHT22, and then the moment of truth... replacing the data node with one of my own boards. Quote Link to post Share on other sites
gsgill112 0 Posted December 28, 2013 Share Posted December 28, 2013 Thanks t0mpr1c3 i just made the raw board , ans its working fine , i was thinking of imtrusion detection kinna application, In India PCB Fab is really costly unless u have an order of like 200 PCB's so i am sticking to Prototyping PCB's . someone from Freescale (mcuoneclipse.com i guess) have a new RF Stack for FREESCALE FRDM platform using nRF24l01+ RF IC, i think that may easy for some basic applications Regards, Gurinder @Gurinder Looks like you are making progress. It hadn't occurred to me to use Energia but that might prove be an easy way to interface some of the sensors. So far I have been looking at the examples in the msprf24 library. I adapted the code very slightly for compilation with msp430-gcc and made some baby steps. I now have 2 launchpads with G2553's on talking to each other from opposite ends of the house and happily blinking their LEDs. I am very pleased with the Spirillis NRF24L01 boosterpacks that I got in the group buy. Next I will try sending a bit of real data, perhaps from a DHT22, and then the moment of truth... replacing the data node with one of my own boards. Quote Link to post Share on other sites
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