Sequent's Sixteen Inputs HAT Adds "Universal" Digital or Analog Inputs to Any Raspberry Pi
Stackable for up to 128 inputs, this HAT aims to connect the Raspberry Pi 5 and other models to "the real world," its creator says.
Sequent Microsystems has opened a crowdfunding campaign for a Hardware Attached on Top (HAT) accessory for the Raspberry Pi 5 and earlier models which adds 16 "universal input" supporting analog or digital signals — and stackable up to eight boards tall, for those who need more.
"Raspberry Pi 5 was recently introduced with gusto," Sequent Microsystems' Mihai Beffa says of the thinking behind his company's latest board design. "While three times faster in computing power, Raspberry Pi 5 remains as powerless as its predecessors if it needs to process analog and digital signals. Sequent Microsystems is connecting it to the 'Real World' by adding up to 128 analog or digital inputs."
That claim of support for 128 "universal inputs" isn't overwrought: while each individual board supports 16 inputs, they're capable of being connected in a stack eight boards tall — nine if you count the Raspberry Pi at the bottom — for a total of 128 inputs. Each input can be configured as an analog or digital input, supporting a range of devices including 1k and 10k thermistors, dry-contact inputs, counter inputs, and 0-10V analog signals at a sampling rate of 500Hz.
"The Sixteen Universal Inputs HAT can be used with any Raspberry Pi or in stand-alone mode, connected through MODBUS to any standard PLC [Programmable Logic Controller]," Beffa writes of the device's capabilities. "Sequent Microsystems has nine other HATs with identical form factor which can be stacked [along] with the Sixteen Inputs."
The board connects to the Raspberry Pi over the I2C bus, leaving the rest of its general-purpose input/output (GPIO) pins free for other uses. Each board includes RS485 input and output ports, a real-time clock with battery backup — not strictly necessary on the Raspberry Pi 5, which includes its own RTC — with hardware watchdog, a resettable fuse, and a dedicated 32-bit processor running at 64MHz. The boards also include a wealth of DIP switches, used for configuration in place of jumpers.
The Sixteen Inputs HAT is now funding on Kickstarter, with physical rewards starting at $59 — a claimed 15 percent discount over eventual retail — and due to start shipping in February this year.