PXR40RM Datasheet, PDF (836/1434 Pages) Freescale Semiconductor, Inc – PXR40 Microcontroller

FlexCAN Module
Table 24-12. FLEXCAN_x_ESR Field Descriptions
Field
Description
0–13 Reserved
14 Tx Warning Interrupt Flag
TWRN_INT If the WRN_EN bit in FLEXCAN_x_MCR is asserted, the TWRN_INT bit is set when the TX_WRN flag transition
from ‘0’ to ‘1’, meaning that the Tx error counter reached 96. If the corresponding mask bit in the Control
Register (TWRN_MSK) is set, an interrupt is generated to the CPU. This bit is cleared by writing it to ‘1’. Writing
‘0’ has no effect.
0 No such occurrence
1 The Tx error counter transition from < 96 to  96
15 Rx Warning Interrupt Flag
RWRN_INT If the WRN_EN bit in FLEXCAN_x_MCR is asserted, the RWRN_INT bit is set when the RX_WRN flag
transition from ‘0’ to ‘1’, meaning that the Rx error counters reached 96. If the corresponding mask bit in the
Control Register (RWRN_MSK) is set, an interrupt is generated to the CPU. This bit is cleared by writing it to
‘1’. Writing ‘0’ has no effect.
0 No such occurrence
1 The Rx error counter transition from < 96 to  96
16 Bit1 Error
BIT1_ERR This bit indicates when an inconsistency occurs between the transmitted and the received bit in a message.
0 No such occurrence
1 At least one bit sent as recessive is received as dominant
Note: This bit is not set by a transmitter in case of arbitration field or ACK slot, or in case of a node sending a
passive error flag that detects dominant bits.
17 Bit0 Error
BIT0_ERR This bit indicates when an inconsistency occurs between the transmitted and the received bit in a message.
0 No such occurrence
1 At least one bit sent as dominant is received as recessive
18 Acknowledge Error
ACK_ERR This bit indicates that an Acknowledge Error has been detected by the transmitter node, i.e., a dominant bit has
not been detected during the ACK SLOT.
0 No such occurrence
1 An ACK error occurred since last read of this register
19 Cyclic Redundancy Check Error
CRC_ERR This bit indicates that a CRC Error has been detected by the receiver node, i.e., the calculated CRC is different
from the received.
0 No such occurrence
1 A CRC error occurred since last read of this register.
20 Form Error
FRM_ERR This bit indicates that a Form Error has been detected by the receiver node, i.e., a fixed-form bit field contains
at least one illegal bit.
0 No such occurrence
1 A Form Error occurred since last read of this register
21 Stuffing Error
STF_ERR This bit indicates that a Stuffing Error has been detected.
0 No such occurrence.
1 A Stuffing Error occurred since last read of this register.
22
TX_WRN
TX Error Counter
This bit indicates when repetitive errors are occurring during message transmission.
0 No such occurrence
1 TX_Err_Counter  96
24-26
PXR40 Microcontroller Reference Manual, Rev. 1
Freescale Semiconductor