Revisiting The RedBearLab IoT pHAT

Howdy, folks. Hope everyone has been okay and has had a good week. Its Friday again!

So my first proper post of 2017 is about the IoT pHAT from RedBearLab, which (if you can recall) I was supposed to review. Due to issues with the HAT firmware that was not possible for quite some time. In the early hours of January 12th, a firmware update was made available which purportedly fixed the issues. On testing it myself, I found this to be the case. So let’s talk about how to get up and running with it. Typically, you’d want to start at this page, but there’s alot of information in there, some of which (thus far) doesn’t seem necessary anymore, so I’m going to try to keep it as linear as I can.

First off, you’ll need an IoT pHAT – not surprisingly. I backed their crowdfunding campaign, but you can now buy one on the RedBearLab store if you don’t already have one. You can get one of two versions – one with headers presoldered and one without headers presoldered. I chose the former version. Note that it only works with Pi boards that have 40-pin headers, so this won’t work with model A and B Pis, but will work with models A+, B+/2/3 and Zero. The steps described in this page were done with the 2016-11-25-raspbian-jessie release, in the desktop environment.

The IoT pHAT comes with some firmware onboard, and this firmware is what had been causing problems. As the firmware update was recently made available, there’s a pretty good chance that your pHAT comes with older firmware (<= v0.3) rather than the current stable version (v0.4). To check the firmware version, run the command cat /proc/device-tree/hat/product. If the result is anything other than “IoT pHAT w/eep_v0.4” then an update is necessary.

To perform the update, you can follow the steps as described here. At this point, ensure that the pHAT is not plugged into the Pi. You can connect your Ethernet cable or WiFi adapter at this point because you’ll need an internet/network connection.

  • Edit config.txt to enable the other I2C bus. Remember to save changes.
  • Download the relevant files (you can do this on the Pi itself or on a PC then transfer the files to the Pi). The files are a .eep file, and a .sh file (the flash script)
  • Now, you can remove/disconnect your network connections, then power the Pi down. Removing the network connections isn’t strictly necessary, but the shutdown is.
  • Plug the pHAT to the Pi and power the Pi up
  • Make the flash script executable with chmod +x eepflash.sh
  • Run the flash script with root privileges (this will take 2-3 minutes to complete)
  • Reboot.
  • You should also remove the line in config.txt which enables the other I2C bus to avoid issues when using a Pi camera

Once this is done, checking the /proc/device-tree/hat/product file should show that the firmware is now v0.4.

From this point, the pHAT works exactly like a regular USB WiFi adapter. Note also that the update is only ever done once, and the pHAT is fully plug and play after that. Using the desktop network applet, I was able to associate with my router’s network, surf the net and generally just do stuff. It seemed very slightly slower than a USB adapter, but maybe that was just me. Bluetooth also worked flawlessly, although I wasn’t able to do anything other than just pair with my cellphone. I think I’ll test out Audio streaming in a later post to see how well it works, but I don’t anticipate any issues.

So in summary, the IoT pHAT is a cheap and fairly painless way to add WiFi and Bluetooth 4 to your Raspberry Pi A+/B+/2/3/Zero. With the v0.4 firmware update the price point is certainly compelling. I’ll hopefully do Audio streaming and possibly a stress test in later posts, so stay tuned!

For my next post, I’ll discuss some mystery hardware I found on Electrodragon and put it to the test.

*walks out of saloon, gun smoking*

Comments

Post a Comment

Popular posts from this blog

Bitbanging SPI on the Raspberry Pi (via spi-gpio)

Image
Hello all and happy holidays to everyone! I’m taking a break off work for the holidays so I have a little bit of time on my hands. I will therefore regale you with tales of my exploits! From my last post, I talked about the somewhat “edge” case where you’d want to add (cheap) Ethernet to a Raspberry Pi, probably the A+ or Zero as the case may be. I haven’t figured out the fixed MAC thing just yet, but I’m working on it. Anyways, after some time, another edge-edge case came to me: The ENC28J60 takes up the only SPI peripheral available on the Pi, so what if you needed to use both the ENC28J60 AND some other SPI device? The Pi’s SPI peripheral has two chip selects, so it is theoretically possible to use the exact same bus while using the first chip select for the ENC28J60 (which it uses by default) and using the second chip select for the other device. However, it goes without saying that network communications require some serious computing firepower so it might cause a bit of a perfo
Read more

Getting Started with Logic Analyzers and Pulseview

Image
Hey all, Been a while. Hope you’ve been up to no good, hm? A couple of days ago, I had to do some low-level I2C work on a bare-metal ATMega328P. Digging out the datasheet, I cobbled a simple I2C driver together, the purpose of which was to permit me write a driver for the particular peripheral which would call the lower-level functions the driver provided (i.e things like i2c_start(), i2c_stop(), i2c_address(), etc etc). When I finished the I2C driver, I tested it out with an MMA8452Q I had lying about and it seemed to work just fine. Believing everything to be dandy, I went ahead and wrote the peripheral driver for the component I was working with. And that was when the funny stuff started. To cut that long story short, it wouldn’t work right when deployed to the hardware. At all. I was in a bit of a bind – the code looked great, no errors no nothing, so it was time to look at the hardware/wire-level end of things. Logic analyzers (in my limited understanding) are tools/instrume
Read more

Enabling SPI1 on the Raspberry Pi B+/Zero/2/3

Image
Me hearties, Let us plunder and pil.. Sorry, wrong blog. Ahem. Hey all, Its been a while. Been busy at work as usual, and haven’t really had much time to write much. As penance, I will post not one but two updates! This particular post is in relation to Raspberry Pi users specifically. I had earlier talked about the vagaries involved in emulating SPI over GPIO in order to get an additional SPI peripheral. It was a moderately involved process, but the rewards were great With the most recent release of the Raspbian Jessie distribution (2016-05-10), a number of improvements have been made to both the desktop parts and the “under-the-hood” parts, perhaps most significantly the kernel. This new release uses Kernel version 4.4, which now adds the ability to use the second hardware SPI peripheral, SPI1, on the Raspberry Pi. This is only available to devices with the 40-pin header (as seen from the title of this post) so users of the original model A and B will probably need to turn to
Read more