PXR40RM Datasheet, PDF (712/1434 Pages) Freescale Semiconductor, Inc – PXR40 Microcontroller

FlexRay Communication Controller (FLEXRAY)
A received frame passes the FIFO filtering if it has passed all three type of filter.
22.6.9.9.1 RX FIFO Frame ID Value-Mask Rejection Filter
The frame ID value-mask rejection filter is a value-mask filter and is defined by the fields in the Receive
FIFO Frame ID Rejection Filter Value Register (RFFIDRFVR) and the Receive FIFO Frame ID Rejection
Filter Mask Register (RFFIDRFMR). Each received frame with a frame ID FID that does not match the
value-mask filter value passes the filter, i.e. is not rejected.
Consequently, a received valid frame with the frame ID FID passes the RX FIFO Frame ID Value-Mask
Rejection Filter if Equation 22-14 is fulfilled.
ID & RFFIDRFMRFIDRFMSK  RFFIDRFVRFIDRFVAL & RFFIDRFMRFIDRFMSK Eqn. 22-14
The RX FIFO Frame ID Value-Mask Rejection Filter can be configured to pass all frames by the following
settings.
• RFFIDRFVR[FIDRFVAL]:= 0x000 and RFFIDRFMR[FIDRFMSK]:= 0x7FF
Using the settings above, only the frame with frame ID 0 will be rejected, which is an invalid frame. All
other frames will pass.
The RX FIFO Frame ID Value-Mask Rejection Filter can be configured to reject all frames by the
following settings.
• RFFIDRFMR[FIDRFMSK]:= 0x000
Using the settings above, Equation 22-14 can never be fulfilled (0!= 0) and thus all frames are rejected; no
frame will pass. This is the reset value for the RX FIFO.
22.6.9.9.2 RX FIFO Frame ID Range Rejection Filter
Each of the four RX FIFO Frame ID Range filters can be configured as a rejection filter. The filters are
configured by the Receive FIFO Range Filter Configuration Register (RFRFCFR) and controlled by the
Receive FIFO Range Filter Control Register (RFRFCTR). The RX FIFO Frame ID range filters apply to
all received valid frames. A received frame with the frame ID FID passes the RX FIFO Frame ID Range
rejection filters if either no rejection filter is enabled, or, for all of the enabled RX FIFO Frame ID Range
rejection filters, i.e. RFRFCTR.FiMD = 1 and RFRFCTR.FiEN = 1, Equation 22-15 is fulfilled.
FID  RFRFCFR_SELSID_{IBD = 0} or RFRFCFR_SELSID_{IBD = 1}  FID
Eqn. 22-15
Consequently, all frames with a frame ID that fulfills Equation 22-16 for at least one of the enabled
rejection filters will be rejected and thus not pass.
RFRFCFR_SELSID_{IBD = 0}  FID  RFRFCFR_SELSID_{IBD = 1}
Eqn. 22-16
22.6.9.9.3 RX FIFO Frame ID Range Acceptance filter
Each of the four RX FIFO Frame ID Range filters can be configured as an acceptance filter. The filters are
configured by the Receive FIFO Range Filter Configuration Register (RFRFCFR) and controlled by the
Receive FIFO Range Filter Control Register (RFRFCTR). The RX FIFO Frame ID range filters apply to
all received valid frames. A received frame with the frame ID FID passes the RX FIFO Frame ID Range
22-128
PXR40 Microcontroller Reference Manual, Rev. 1
Freescale Semiconductor