emSTAMP Helium (Rev3)
19/23
PD21
SPI_MOSI
PD24
SPI_CS
PB29
BT_TXD
PB28
BT_RXD
PB31
BT_CTS
PC0
BT_RTS
PD20
WIFI/BT_TXD
PD19
WIFI/BT_RXD
PB30
WIFI/BT_EN
PB2
WIFI/BT_IRQ#
PA29
WIFI/BT_RST#
6.6
TPM
The SBC includes a TPM that may securely store cryptographic keys and perform
cryptographic actions.
The TPM is connected to the I²C interface TWI0 of the CPU module (PD29 and PD30). PD 28 is
used as reset signal for the TPM.
6.7
CAN
The processor on the Helium module includes a CAN controller, which is compliant to the CAN
protocol specification 2.0 Part A, B and ISO 11898-1 supporting both standard and extended
message frames. The LVTTL transmit and receive signals of the CAN channel are directly
connected from the Helium module to the pin header. Additionally, 3.3 V supply and GND are
provided. The signal level is 3,3V. The maximum baud rate is 1Mbps.
For a connection to a CAN network a transceiver must be connected to the pin header.
Emtrion
’
Pin
Signal
1
3.3V
2
GND
3
TX
(PC1)
4
RX
(PC2)
5
n/c
6.8
Debug console
The Helium module has a serial port which is used for debugging. The serial port is integrated
in the processor and available as LVTTL level. The connections are ESD and EMI protected. The
pinout is compatible to FTDIs TTL-232R-3V3 USB-to-serial cable.