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10% Cyber Monday Discount Coupon

2009-11-30T08:12:00.002-05:00

We're pleased to announce a 10% discount off your entire order for Cyber Monday! There is no minimum or maximum order total, but the coupon is limited to one redemption per customer and in-stock items. Just enter coupon code "DECM" (without the quotes) at the end of your checkout to redeem!

New stuff after so long...

2009-11-16T17:01:00.005-05:00

So it's been a really long time since I posted anything, so I figured what better way than with some new goodies.

This is the breakout for Nordic's nRF24LE1 microcontroller. It's got an 8051 core and a 24L01+ radio on the chip, in addition to 15 GPIO, 11 ADC inputs, PWM, SPI, UART, 2-wire, and a bunch of other goodies!

And, as usual, there is the RP-SMA version for those who need more range than the chip antenna version can offer.

New products added to store!

2009-01-07T15:56:00.001-05:00

I would first like to thank everyone who has made a purchase at our store so far! I'm trying my best to keep some fresh products coming down the pike, so check out these new goodies!

Breakout for Nordic's new nRF24L01+ chip, which takes the nRF24L01 and adds a 250 kbps mode, longer range, and better sensitivity. The nRF24L01+ breakout with chip antenna version includes an on-board ceramic antenna for convenience.

For those who yearn for long range, you can go for the nRF24L01+ breakout with RP-SMA connector, which allows you to interface to high-gain RP-SMA antennas!

Speaking of RP-SMA antennas, we now carry a 5" 2.4 GHz RP-SMA duck antenna!

Store is open!

2008-08-20T20:56:00.004-04:00

It's an exciting day! The new e-store, available at http://store.diyembedded.com/ is open with a whopping two products! I will be expanding products as fast as I can, but for the time being here's what we have.

An updated breakout of the prior nRF24LU1 module, the nRF24LU1 Stamp Breakout with Chip Antenna plugs into an 18-pin wide DIP socket and has all of the important support components to get you up and running!

If the range of the chip antenna module isn't enough for you, I've also developed the nRF24LU1 Stamp Breakout with RP-SMA Connector. This guy has all of the same features as the chip antenna module, but it allows you to plug in high-gain external antennae to get longer range!

Also, I've set up a support forum that can be found at http://forum.diyembedded.com. There are forums set up for the products I sell, as well as other forums for general interest. Any comments are welcome!

Bootloader v0 release and maybe boards for sale

2008-05-14T20:46:00.006-04:00

I am considering selling the extra boards that I have right now. I have 15 boards that I have not soldered on, etc. I am thinking about selling these boards for $40 (fully assembled and tested). If you wanted the programmer board with a cable, that would probably be another $10. I haven't been able to successfully write a programmer program because my parallel port is messed up. I have one I think works, but I would have to either get another parallel port (not too expensive) or else let somebody else try it. If anyone would be interested in purchasing a board, I plan on burning in a bootloader program previous to shipping the board, which uses the RS-232 port to upload user programs. Please leave comments if you'd be interested in a board so I can gauge response to see if it's worth ordering the extra parts.

The on-chip bootloader is written in assembly (yuck) and lives in the highest page of flash (starts at address 0x3E00). It uses the UART to communicate to the program that was written for the PC in C# to get its data. The program was written with the potential to be expanded, but that framework hasn't been developed yet in order to get it done quickly.

The only rub with using the bootloader is that, unless you can time hitting the RESET button really well, you need to add a green-wire fix to allow the RTS line from the RS-232 port to control the RESET pin on the nRF24LU1. This is relatively easy, and I will put up a schematic and pictures if anybody were to need it.

On-Chip Bootloader
The bootloader was written to be compiled with AS31, which can be downloaded (with a special version of SDCC) here. The link to the .zip file containing the makefile, asm source file, and compiled hex file can be found here.

PC-Side Bootloader
The bootloader program on the PC-side was written in C# for Windows (Linux guys are on their own). This version was written with Visual Studio 2005 Professional, but it can also be compiled using Visual C# 2008 Express, which is a free download from here. The link to the .zip file containing the C# project, source files, and executable file can be found here.

Edit: I now have nRF24LU1 breakout boards for sale at http://store.diyembedded.com!

nRF24LU1 board is alive and well

2008-04-12T16:17:00.007-04:00

So I swear I'm not dead. I have been working hard on writing code for the 24LU1 board. I have a lot of software working now, and I just wanted to post a video of this guy in action. The only problems I've found with the board are that the /RST LED was supposed to be wired in active low configuration, but I ended up doing it like all the other LEDs (it's on all the time *except* when you push the reset button).

Edit: I now have nRF24LU1 breakout boards for sale at http://store.diyembedded.com!

New Blog Subscription Link and Boo on Advanced Circuits

2007-12-03T11:12:00.001-05:00

After getting a request to have a subscription to the blog, I've finally found a way to do it by using a Google group. All you have to do is put your email into the box on the right side of the main page, click "Subscribe", and then click the link in the email that is sent to you to confirm the subscription.

So I was initially going to send the nRF24LU1 board off to Advanced Circuits, but apparently they don't allow panelization on their boards. Totally uncool. So I cancelled my order and I'm going to go with Gold Phoenix this time around, and I'm also going to have them make the programmer/prototyping board I'm working on. That should be up in a day or two. Hopefully this will actually work.

Edit: I now have nRF24LU1 breakout boards for sale at http://store.diyembedded.com!

New nRF24LU1 board on the way...

2007-11-25T18:57:00.001-05:00

Hey guys. Sorry for the delay, but I've been pretty busy making a layout for the new nRF24LU1 chip from Nordic. I have sent the board off to have some prototype PCBs made (12 for the first run in case I made some mistakes in the schematic/layout). For all of you guys that are interested, I have published the schematic and layout. Hopefully I will be selling these guys once I get them up and working properly.

Edit: I now have nRF24LU1 breakout boards for sale at http://store.diyembedded.com!

New project with new chip (nRF24LU1)

2007-10-19T09:18:00.003-04:00

I have decided to use one of the suggestions from the previous post for the next project. In case you didn't know, Nordic recently released a new chip that takes the 24L01 and on the same chip adds an 8051 core, 16 kB of EEPROM for program memory, and an AES encryption coprocessor. It also has 6 GPIO pins, that can also be multiplexed with other features, such as hardware SPI and UART.

I am going to try to lay out a board and get SDCC or some other compiler to generate code for the 8051 core. If any of you guys are familiar with 8051 coding (especially in C using some freely available compiler), then I would definitely like to hear from you (the easiest way is to make comments on this post).

This project is going to be quite an undertaking, and once I get my stuff working I will try to start making some boards for purchase. There will also have to be some sort of programmer module, since programming the chip initially requires that it be done over SPI. If I can get a bootloader going, I am going to try to get USB up and running on the chip, so that it can be programmed that way.

It may be a while before I get this done (or even a large amount of progress). Be patient and watch for updates occasionally.

Edit: I now have nRF24LU1 breakout boards for sale at http://store.diyembedded.com!

Suggestions on new tutorials?

2007-09-03T00:21:00.000-04:00

I would like to ask you guys, the readers of my tutorials, what you would like to see as the next tut? I'm not limiting it to wireless stuff, although that's certainly fair game. If there are any particular applications that you have been wanting to dive into and take a look at, but aren't quite sure how to do, suggest them here. Just a few I've thought about are remote controls, wireless audio transmitter (high difficulty level), sensor networks (also pretty tough), and a few others. Feel free to post comments on this thread (anyone can post) and let me know what you'd like to see!

ARC4 tutorials posted

2007-08-14T22:11:00.000-04:00

Long overdue, I have finally completed the tutorials for ARC4 ("Alleged RC4") cryptography for use with RF wireless transmissions via the nRF24L01. Now you can secure the data that you're sending through the air in a similar format to WEP and WPA security protocols. I have created implementations in C for PIC and ARM architecture (PIC18F452 and LPC2148, respectively) just like all of the other tutorials. Now you're in the big leagues!

Check out the links to the zip files here: LPC2148 and PIC18F452.

Status update and new 24L01 data sheet released

2007-08-10T23:30:00.001-04:00

I promise that I haven't fallen off the face of the Earth. I haven't been able to work on tutorials for the last month or so because I started work right in crunch time of a product cycle. Blah. I am still around to help if you guys email me, though (and a few of you have). I'm going to try to finish up that ARC4 tutorial. I also sampled some Wolfson WM8737 ADC chips so I can try to chase after my DIY wireless guitar transmitter. If I can get something going, I'll let you guys check it out.

In 24L01 news, Nordic has now (after over a year of secrecy) revealed that there are hidden features on the 24L01. I kinda knew that there was a reason that they still had a draft spec out, but now they have released a new one which can be found here. They have released functionality for dynamic payload length, selective acknowledge, and payload on auto-ack. These are some great features that would have been even better had they have been released from the get-go. I suppose now I get to write a new version of Tutorial 0 and the include library...

Moving...

2007-07-13T12:26:00.000-04:00

Hey guys and gals. Just wanted to let you guys know that I'll be moving next week, and I've been packing this week. I've got the code to the intro security code up and running, but I still have to complete the write-up. I'm hoping to be able to get that completed sometime next week or weekend, if I get some spare time.

New tutorial in the works

2007-06-26T12:00:00.000-04:00

Sorry about the long layoff - I have been incredibly busy with my class and job interviews over the last few weeks. I just wanted to let you guys know that I have another tutorial in the works for wireless security using the ARC4 stream cipher algorithm. For those of you that aren't familiar with ARC4, it's a hack of the RC4 algorithm developed by the RSA. RC4 is used very widely in many crpytostreams, including SSL and WEP. I'm hoping to have it done and written up in a week or two. If all goes well, I'll have implementations for both the LPC2148 and PIC18F452 in conjunction with the nRF24L01 and ARC4.

Edit: The tutorial has been completed and is linked at this post toward the bottom: http://www.diyembedded.com/2007/08/arc4-tutorials-posted.html

nRF24L01 tutorials 1-3 for the PIC completed

2007-06-04T00:12:00.000-04:00

Well, I finally got it done! Tutorials 1-3 for the nRF24L01 have been completed with write-ups for the PIC line of processors (PIC18F452 in these). I forgot to change one thing in the project build options though, and it will likely make some weird directories on your machine if you try to compile the source. In MPLAB, click Project->Build Options->Project. Next, click the "Directories" tab and in the "Show directories for:" drop-down box, change "Output Directory" and "Intermediate Directory" to their default values by choosing the appropriate option and hitting the "Suite Defaults" button (you will have to do it for both).

The links to the .zip files for each of the projects can be found here: Tutorial1, Tutorial2, and Tutorial3.

The first guest tutorial!

2007-06-03T20:31:00.000-04:00

I would like to personally thank Evert Dekker for sending me a really cool tutorial on getting the 24L01 up and running using BASCOM-AVR. Check out the .zip file here.

And remember, if any of you guys have written up any cool software using the 24L01 or anything else for that matter, feel free to send it to me with an accompanying write-up and I will be happy to post it here!

Getting bogged down...

2007-05-31T00:29:00.000-04:00

So my final class I'm taking for my Master's degree is underway and is absolutely killing my free time. I have translated all three of the tutorials over to the PIC architecture, but I still haven't updated the write-ups. Some will take a little longer than others (the first one is by far going to be the most work). If you guys really want the code, send an email to brennen *at* diyembedded *dot* com. Otherwise, I'll try my best to get those write ups done this week/weekend if I have a minute away from HW and the girlfriend :) .

PIC code now working

2007-05-22T09:08:00.000-04:00

I have now translated the code for Tutorial 1 over to the PIC 18F452. Many of you may know that this chip has been replaced by the 18F4520, but the code should still work just fine with minor modifications. I have to finish the write-up, but hopefully I'll have it posted in the next couple of days for you PIC lovers who wanna get down with an nRF24L01.

nRF24L01 tutorials for PIC coming soon

2007-05-19T14:23:00.000-04:00

Well, I'm finally trying to get the tutorials translated over to the PIC line of microcontrollers. I'm programming in Microchip's C18 C compiler with MPLAB. I will be doing my development on an 18F452 (which has been replaced by the 18F4520, but is still basically code-compatible). I currently have the delays, SPI, and UART all working, so now it's just a matter of time to in testing the nRF24L01 library to see if I can get that working, and then integrate the main programs. Hopefully that should get you not-so-32-bit-inclined people out there up to speed with the nRF24L01 library!

Edit: The tutorials have been completed and are linked at this post toward the bottom: http://www.diyembedded.com/2007/06/tutorials-1-3-for-pic-completed.html.

Considering an audio tutorial

2007-05-16T15:42:00.000-04:00

If I can get some spare time in the next short while, I'm considering developing a tutorial that would implement a wireless audio transmitter using my normal hardware (LPC2148 and nRF24L01) with a couple of buffers. I would just be using the 2148's built-in A/D and D/A converters, so the quality probably wouldn't be that great. I think it would be a cool thing for you guys that dig audio (like me), and it may be a good place to get you started on moving up into nicer components (audio-spec ADCs and DACs). I'd love to hear your comments or suggestions!

Tutorial 3 completed and uploaded

2007-05-07T14:26:00.000-04:00

OK, I have another one for you guys. This tutorial shows you how to use all 6 pipes on the 24L01 (the idea was actually prompted from some questions over in the Sparkfun forums). Check out the zip file here.

Tutorial 2 uploaded finally

2007-04-30T16:05:00.000-04:00

So I finally got the write-up and code all worked out for Tutorial 2. In this tutorial, we will be exploring Enhanced Shockburst. Check this one out if you want a more robust link! NOTE: You should read Tutorial 1 before you read Tutorial 2. Tutorial 2 builds of Tutorial 1 heavily and is nearly identical in software (less than 15 lines total). Tutorial 2 can be found here.

In case you couldn't get Tutorial 1 downloaded, try the link in the post below and it should be working now. If not, feel free to contact me at brennen *at* diyembedded *dot* com.

New 24L01 tutorial uploaded

2007-04-28T01:55:00.000-04:00

I have finished up the next tutorial in the nRF24L01 series. This tutorial outlines the procedures necessary for getting a link up and running with the nRF24L01 chips. Since there are a PDF and and source code, I have created a zip file, which you can download here.

Tutorial 0 for the nRF24L01 uploaded

2007-04-26T20:05:00.000-04:00

OK, so I got studious tonight and decided to finish up Tutorial 0 for the nRF24L01. It is basically just background on the 24L01 chip and my preferred breakout, the MiRF-v2 from Spark Fun. I tried to give information on every aspect of the chip I could, including helping to explain connections, setup, instructions, registers, etc. I also tried to give hints and help on snags that I have run into in the past using the chip. Check out this tutorial here.

Two more tutorials are coming, and they are pretty much intro tutorials to get a simple link going. In the first tutorial, I will show you how to take data from the serial port of your computer port and send it to a remote microcontroller over the RF link, and then have the remote microcontroller send it back to the PC. In the second tutorial, I take basically the same code, but add in some functionality for Enhanced Shockburst transmission/reception with auto-acknowledgement and -retransmit.

Making progress

2007-04-26T18:31:00.000-04:00

Well, I have signed up for some webspace and a new domain name. The tutorials have been written and tested in software, but still require some documentation. I'm hoping to have them out by the end of the week. This site will be going under considerable renovation over the next little while until I get a design I really like.