Pseudonymous maker “Valdez” has built-in an otherwise-unsupported DSC Neo alarm system into Residence Assistant — by creating an Espressif ESP32-based “digital keypad” which might bodily work together with the alarm panel.
“In late 2023, Chamberlain began blocking the MyQ storage door integration from Residence Assistant,” Valdez explains of his expertise with unsupported good dwelling units. “I realized from the MyQ blockade that if you happen to can work together with a tool bodily, i.e. by studying a easy LCD display screen and pushing some buttons, regardless of how sturdy the encryption is between that gadget and its mothership, the data to and out of your eyes and fingers should be in an unencrypted type that may then be intercepted or injected remotely.”
A customized service and an Espressif ESP32 dev board has acquired an unsupported alarm built-in into Residence Assistant. (📷: Valdez)
That is the important thing behind Valdez’ technique of integrating units into Residence Assistant with out official help from the producer. Taking the DSC Neo alarm panel aside, Valdez started tracing the connectors to the show earlier than analyzing the indicators with “a $20 logic analyzer” — adequate for the job at hand, delivering the data the maker wanted to seize the information on the way in which to the show and decode it into textual content.
That dealt with studying the alarm, however Valdez nonetheless wanted to regulate it. By probing every of the alarm panel’s 25 buttons and connecting the logic analyzer, Valdez was capable of confirm that the panel’s controller was quickly scanning the keypad matrix. “The character of the scanning matrix meant I could not simply pull the X/Y coordinates excessive/low with the ESP32,” Valdez notes, “I must join the 2 coordinates of the matrix collectively so the scanning sign would attain the opposite coordinate line for the button I needed to push. Nevertheless it may nonetheless be executed with solely 10 GPIOs [General Purpose Input/Output pins] by making a matrix of switches.”
An preliminary relay-based prototype proved just a little too cumbersome, although demonstrated the idea was sound. (📷: Valdez)
A proof-of-concept constructed round a matrix of ten 5V relays demonstrated that management was potential, however the construct wasn’t elegant. “The relay modules and wires had been ridiculously cumbersome, giant, and required a separate 5V energy provide,” Valdez explains. “though I did benefit from the audible clicks of the relays like an early pc clicking away.” The answer was a customized PCB with ten Sharp PC817 optocouplers enjoying host to an Espressif ESP32 dev board.
With some intelligent code — together with a binary sensor which might detect when specific zones have triggered — Valdez’ venture was full, including a digital keypad into Residence Assistant which supplies full distant management over the alarm system and stay standing reviews on every of its zones. “They’re very aware of when the zone faults,” Valdez claims of the Residence Assistant dashboard readings. “Rather more responsive than alarm.com is.”
The complete venture write-up is obtainable on Hackaday.io, with extra data within the Residence Assistant discussion board.