A handheld upgrade tool comprising: nonvolatile memory; an information element; an I/O port connector; a sensor port connector individually attachable to a sensor port of a patient monitor in lieu of a sensor, the sensor port electrically connected to a processor board comprising a plurality of firmware instructions executable by the processor board to calculate a plurality of physiological parameters in response to a sensor signal received from the sensor; and a tool digital signal processor,DSP, configured to: authenticate the processor board, wherein to authenticate the processor board the tool DSP is configured to: verify that a valid processor board is connected to the sensor port by performing a successful encrypted handshake with the processor board, wherein an encrypted handshake is successful if the handheld upgrade tool recognizes the processor board and the processor board recognizes the handheld upgrade tool, and if the encrypted handshape is successful, determine that a board type of the processor board matches an upgrade tool type of the handheld upgrade tool, and if the board type of the processor board is determined to match the upgrade tool type of the handheld upgrade tool, perform parameter upgrade administration, wherein parameter upgrade administration includes reading the available parameters from the processor board and verifying a tool upgrade count; and if an upgrade tool specific parameter is unavailable on the processor board and if the tool upgrade count is not zero, make available the upgrade tool specific parameter to the processor board for output by the patient monitor, wherein making the upgrade tool specific parameter available for output by the patient monitor enables the processor board to calculate at least one additional physiological parameter in response to the sensor signal received from the sensor. nonvolatile memory; an information element; an I/O port connector; a sensor port connector individually attachable to a sensor port of a patient monitor in lieu of a sensor, the sensor port electrically connected to a processor board comprising a plurality of firmware instructions executable by the processor board to calculate a plurality of physiological parameters in response to a sensor signal received from the sensor; and a tool digital signal processor,DSP, configured to: authenticate the processor board, wherein to authenticate the processor board the tool DSP is configured to: verify that a valid processor board is connected to the sensor port by performing a successful encrypted handshake with the processor board, wherein an encrypted handshake is successful if the handheld upgrade tool recognizes the processor board and the processor board recognizes the handheld upgrade tool, and if the encrypted handshape is successful, determine that a board type of the processor board matches an upgrade tool type of the handheld upgrade tool, and if the board type of the processor board is determined to match the upgrade tool type of the handheld upgrade tool, perform parameter upgrade administration, wherein parameter upgrade administration includes reading the available parameters from the processor board and verifying a tool upgrade count; and if an upgrade tool specific parameter is unavailable on the processor board and if the tool upgrade count is not zero, make available the upgrade tool specific parameter to the processor board for output by the patient monitor, wherein making the upgrade tool specific parameter available for output by the patient monitor enables the processor board to calculate at least one additional physiological parameter in response to the sensor signal received from the sensor. authenticate the processor board, wherein to authenticate the processor board the tool DSP is configured to: verify that a valid processor board is connected to the sensor port by performing a successful encrypted handshake with the processor board, wherein an encrypted handshake is successful if the handheld upgrade tool recognizes the processor board and the processor board recognizes the handheld upgrade tool, and if the encrypted handshape is successful, determine that a board type of the processor board matches an upgrade tool type of the handheld upgrade tool, and verify that a valid processor board is connected to the sensor port by performing a successful encrypted handshake with the processor board, wherein an encrypted handshake is successful if the handheld upgrade tool recognizes the processor board and the processor board recognizes the handheld upgrade tool, and if the encrypted handshape is successful, determine that a board type of the processor board matches an upgrade tool type of the handheld upgrade tool, and if the board type of the processor board is determined to match the upgrade tool type of the handheld upgrade tool, perform parameter upgrade administration, wherein parameter upgrade administration includes reading the available parameters from the processor board and verifying a tool upgrade count; and reading the available parameters from the processor board and verifying a tool upgrade count; and if an upgrade tool specific parameter is unavailable on the processor board and if the tool upgrade count is not zero, make available the upgrade tool specific parameter to the processor board for output by the patient monitor, wherein making the upgrade tool specific parameter available for output by the patient monitor enables the processor board to calculate at least one additional physiological parameter in response to the sensor signal received from the sensor.