Datasheet

TJA1085 All information provided in this document is subject to legal disclaimers. © NXP B.V. 2012. All rights reserved.
Product data sheet Rev. 1 — 23 October 2012 17 of 61
NXP Semiconductors
TJA1085
FlexRay active star coupler
6.9.1.3 Branch_Disabled
An overtemperature event (TEMP_HIGH flag set) triggers a transition from
Branch_Normal to Branch_Disabled in all branches.
If an overtemperature event triggered the transition from Branch_Normal to
Branch_Disabled, all branches return to Branch_Normal when the overtemperature
problem has been resolved (TEMP_WARN flag reset).
The ‘Branch_Disabled’ and ‘Branch_Normal’ commands can be used to enable/disable
individual branches. A host command is also available to trigger a transition from
Branch_Disabled to Branch_TxOnly1 (‘Branch_TxOnly').
If a branch switches from Branch_Disabled to Branch_LowPower because the TJA1085
has entered AS_Standby or AS_Sleep, it will return to Branch_Disabled when the
TJA1085 enters AS_Normal.
6.9.1.4 Branch_FailSilent
A branch switches to Branch_FailSilent:
- from Branch_Normal if a branch is clamped (Clamp_BRx flag set), provided
clamp-detection is enabled (bit CLAMP_DET set; see Table 8
)
- from Branch_Normal if a transmit error (TxE_BRx = 1) is detected, provided
autonomous error confinement is enabled (bit AEC set; see Table 8
)
- from Branch_TxOnly1 if a transmit error (TxE_BRx = 1) is detected.
The branch remains in Branch_FailSilent until idle is detected on all branches, when it
switches to Branch_TxOnly1 (a ‘Branch_TxOnly’ command is needed in HC mode).
6.9.1.5 Branch_TxOnly1
A branch switches to Branch_TxOnly1:
- from Branch_Disabled in response to a ‘Branch_TxOnly’ command (HC mode)
- from Branch_FailSilent in response to a ‘Branch_TxOnly’ command when all branches
are idle (HC mode)
- from Branch_FailSilent when all branches are idle (AP mode)
A branch switches from Branch_TxOnly1:
- to Branch_Normal when a transmission ends without error
- to Branch_FailSilent if a transmit error is detected (TxE_BRx = 1)
6.9.1.6 Branch_TxOnly2
This mode is purely host controlled. A branch switches to Branch_TxOnly2 only in
response to a ‘Branch_TxOnly’ command issued in Branch_Normal mode. The branch
remains in Branch_TxOnly2 mode until a ‘Branch_Normal’ command is received.
6.9.1.7 Branch_Normal
A branch switches to Branch_Normal:
- from Branch_LowPower when the TJA1085 enters AS_Normal mode (provided it was
not in Branch_Disabled before the transition to Branch_LowPower mode)