Raspberry Pi Developers Introduces New Expansion Board Specifications for Raspberry Pi B +
Not so long ago, a new "raspberry" was introduced - a miniature PC, with expanded capabilities compared to the Raspberry Pi A and B. Now, developers have introduced specialized expansion cards for the Raspberry Pi B +, which are called HATs (Hardware Attached on Top).
In general, expansion cards were issued earlier by third-party developers, but all this did not always work well, and not always correctly, so the creators of Malinka decided to standardize the expansion cards. At the same time, you can still use your own methods of connecting boards to the Raspberry Pi, developers do not insist on using their own methods.
Separately, it is worth noting that on the new Raspberry Pi the old expansion cards will work, since the first 26 pins of the GPIO model B + are similar to the previous pinout. Well, and additional pins provide additional features.
The base of the HAT is a rectangular board with smooth corners and four holes for mounting the board. Holes, of course, coincide with similar holes in B +, plus the board has its own 40W GPIO connector.
To automatically connect the board without dancing with a tambourine, 2 dedicated pins (ID_SD and ID_SC) are used, reserved for I2C EEPROM. The latter stores information about the manufacturer of the board, GPIO settings, and the ' device tree ' - hardware information that allows Linux to automatically load the necessary drivers.
All necessary specifications for HAT are uploaded to GitHub .
The developers have already created a perfectly working HAT prototype with a universal connector.
Ready-made connector sets will be sold by Toby Electronics and other retailers:
HLE-120-02-F-DV-BE = £ 0.57 each (surface mount connector without locating peg)
HLE-120-02-F-DV-BE-A = £ 0.67 each (surface mount connector with locating peg)
SSQ-120-02-FD = £ 0.56 each (extension header short pins)
SSQ-120-03-FD = £ 0.64 each (extension header long pins)