SimpleSerial

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SimpleSerial is the name given to the default communication protocol used by NewAE Technology Inc.'s demos.

Commands

Command Example Description In/Out ENC AUTH
h h00\n Select stack / hardware to use (if supported). In M M
k k2b7e151628aed2a6abf7158809cf4f3c\n Set encryption key; possibly trigger key scheduling In Y Y
m m00\n Select cipher mode (if supported) In M M
p p126110475e17505a6966be70c89a829c\n Send input plain-text, cause encryption In Y Y
r r10000000000000000000000000000000\n Result of function - if encryption is encrypted result, if auth is '0..0' or '100..0'. Out Y Y
t t640a4a78332a8dee2bce15132ec44027\n Authentication challenge (i.e., expected AES result if using AES as auth-method) In N Y
v v\n Check protocol version (no reply on v1.0; ACK on v1.1) In Y Y
x x\n Clears Buffers (resets to 'IDLE' state), does not clear any variables. In Y Y
z z00\n ACK - Command processing done (with optional status code) Out Y Y

Y = YES, Command support for application.

N = NO, Command not supported for application.

M = MAYBE, Command may be supported depending on build target.

Encryption Application

The encryption application provides a simple method to encrypt a plaintext into a ciphertext. This application was the original "simple serial". The following operations are performed:

  1. Load encryption key with 'k' command (for example, k2b7e151628aed2a6abf7158809cf4f3c\n sets key to 2b7e151628aed2a6abf7158809cf4f3c).
  2. Set input text to encryption module with 'p' command. Device encrypts input text, and toggles the I/O trigger line during the encryption operation.
  3. The ciphertext is returned with the 'r' command.

Authentication Application

The authentication application does not expose the result of the encryption. Instead, the result is used only in authentication mode, where the following operations are performed:

  1. Load encryption key with 'k' command (for example, k2b7e151628aed2a6abf7158809cf4f3c\n sets key to 2b7e151628aed2a6abf7158809cf4f3c).
  2. Set the authentication challenge with 't' command.
  3. Set input text to encryption module with 'p' command. Device encrypts input text, and toggles the I/O trigger line during the encryption operation.
  4. Device compares the resulting ciphertext with the challenge set with 't'.
  5. If challenge and ciphertext match (auth OK), device responds with 'r1000000000000000\n'. If do not match, device response with 'r0000000000000000\n'.

The authentication application is the default shipped with ALL programmed modules.