TLE9221SX Datasheet, PDF (18/91 Pages) Infineon Technologies AG – FlexRay Transceiver

TLE9221SX
Host Interface and Status Information Register
6
Host Interface and Status Information Register
The Host Interface is the main interface for:
• Selecting and controlling the operation modes of the TLE9221SX by host commands.
• Receiving status information of the TLE9221SX at the ERRN output pin.
• Retrieving diagnostics information of the TLE9221SX by reading the Status Information Register.
The Host Interface is operational when the reference voltage uV_IO is in its functional range. In case the supply uV_IO
is in undervoltage condition, the Host Interface is blocked and the operating mode of the TLE9221SX FlexRay
transceiver is automatically set to BD_Sleep mode (compare with Chapter 9.3).
6.1
Host Commands
The digital inputs EN and STBN have dual functionality:
• EN and STBN are used to select the operating mode.
• EN and STBN are used to trigger the read-out of the Status Information Register.
The STBN, EN and all other digital inputs of the TLE9221SX are level-triggered and protected with a glitch input
filter. Additionally, a digital input filter is provided at the mode selection pins STBN and EN.
To get a valid host command, which triggers a change of the operating mode, the external signals at the pins EN
and STBN need to be stable at least for time t ≥ dBDLogic_Filter. Signal changes with a smaller pulse width than the
internal filter time t < dBDLogic_Filter are not considered valid host commands and the TLE9221SX remains in its
previous operating mode.
Within the time for mode change t = dBD_ModeChange the FlexRay transceiver TLE9221SX changes to the selected
mode of operation (see Figure 10). All output signals are valid after the mode transition and when the time for
mode change t = dBD_ModeChange has expired.
STBN
EN
t < dBDLogic_Filter
BD_Normal
t = dBDLogic_Filter
t = dBD_ModeChange
mode transition
100% uV_IO
50% uV_IO
0% uV_IO
t
100% uV_IO
50% uV_IO
0% uV_IO
t
BD_Standby
host command detection
mode change
Figure 10 Example of a valid host command
Note: The time for mode change has to be considered for every change of the operation mode. All definitions in
this data sheet are made considering the time for mode change dBD_ModeChange, even if the time for mode
change is not explicitly mentioned, for example in logical status tables, mode diagrams or in elementary
timing diagrams.
Data Sheet
18
Rev. 1.10, 2013-07-15