VCC | Power | Power Supply. Proper decoupling is required. |
GND | Power | System Ground. |
MISO | Output | Host In Client Out. This pin serves as the SPI Data Output from the
TPM. |
MOSI | Input | Host Out Client In. This pin serves as the SPI Data Input to the
TPM. |
PIRQ# | Open Drain Output | SPI Interrupt Pin, active-low. This pin is used by the TPM to assert
interrupts. If unused, it is recommended to tie this pin to ground
directly or through a 4.7 kΩ resistor. |
SPI_CLK | Clock Input | Input Clock to drive the SPI bus. It is recommended to assert this
pin high for power savings when the TPM is not in use. |
SPI_CS# | Input | SPI_CS# Chip Select, active-low. The TPM device will be
selected when the chip select is asserted LOW. |
SPI_RST# | Input | SPI Reset Pin, active-low. Pulsing this signal low resets the
internal state of the TPM, and is equivalent to the removal/restoration
of power to the device. The required minimum reset pulse width is 2 µs.
On power-up, it is critical that the reset be kept active-low until the
VCC and SPI_CLK stabilize. To be compliant with TCG
requirements, this pin needs to be tied to the system reset. TPM_Init is
indicated by asserting this pin. |