h1. PN544 h2. Links The "us-21-Breaking-Secure-Bootloaders.pdf":https://i.blackhat.com/USA21/Wednesday-Handouts/us-21-Breaking-Secure-Bootloaders.pdf presentation has some information on the PN553 bootloader, firmware and architecture and the "PN553 bears similarities with the PN547, PN548, PN551 and PN5180". So some of the information may apply to the PN544 as well.