Have you ever wondered whether it is possible to use two HATs at the same time on your single board computer, the Raspberry Pi (RBPi)? Alternatively, how to access the GPIO pins with the HAT sitting atop your RBPi? People who design HATs also faced the same problems and as a solution designed Hack3r, the Black HAT for the RBPi. Initially, this was a tool for debugging HATs under design, but later on, the debugging tool took on the form of another useful HAT.
HATs for the RBPi are Hardware Attached on Top boards with special design. One of their specialties is automatic detection by the host RBPi when the HAT is plugged in. Depending on the settings indicated by the particular HAT plugged on, your RBPi can adjust its hardware and software settings to allow the HAT to function properly. That is, if the HAT functions as intended.
Trouble starts when the functioning of the HAT and your expectations of its functioning do not match. As the design of the HAT makes it sit firmly atop the RBPi, there is practically no access to the pins of the RBPi underneath, making troubleshooting an impossible task. With the Hack3r available, you plug in your HAT into it, while connecting the Hack3r to your RBPi with a flat ribbon cable and connectors. Not only this, the Hack3r has additional pins, two sets of 40 pins each mirroring the 40-pin GPIO set of the RBPi.
This nifty little tool comes unsoldered. Therefore, you will need a good soldering iron, one preferably with a fine tip and a fair amount of solder. You will also need plenty of patience while soldering the 120 points, which include the two sets of 40 pins for the GPIO, and one set of 40 pins for the ribbon cable. The pins supplied are individual pins, and you must make sure to solder them in straight. In case this looks tough for you, substitute the individual pins with three strips of 2×20 pin male headers. Use open type headers as there is no polarity involved and the plastic base holds the pins upright and straight.
The Hack3r board comes with all the GPIO pins labeled neatly with their function, the BCM pin number and the physical pin number. Therefore, while troubleshooting the board, one look at it is enough to tell you a lot about the signal you are accessing. There is no need to keep another reference diagram for cross checking the signal source.
If you have two Hack3r boards, they will help when you need to use two HATs at the same time. Of course, you must make sure the HATs are not using the same GPIO pins simultaneously. One of the Hack3r boards connects to the RBPi with a ribbon cable, while the second Hack3r connects to the first Hack3r board with the second ribbon cable. Now you can plug in one HAT on to the first Hack3r and the second HAT on the second Hack3r.
In conclusion, the Hack3r is a wonderful and nifty little debugging tool for the RBPi to help you at times when you are developing or troubleshooting your HAT.
