MC9S12VR-Family - Data Sheet - Freescale Semiconductor

LIN Physical Layer (S12LINPHYV1)
15.3.2.8 LIN Interrupt Flags Register (LPIF)
Module Base + Address 0x0007 Access: User read/write 1
7 6 5 4 3 2 1 0
R 0 0 0 0 0 0 0
LPOCIF
W
Reset 0 0 0 0 0 0 0 0
15.4 Functional Description
15.4.1 General
= Unimplemented
Table 15-11. LPIF Fields Description
The LIN Physical Layer module implements the physical layer of the LIN interface. This physical layer
can be driven by the SCI (Serial Communication Interface) module, the timer for bit banging or directly
through the LPDR register.
15.4.2 Slew Rate Selection
Figure 15-9. LIN Interrupt Flags Register (LPIF)
1 Read: Anytime
Write: Writing ‘1’ sets the flags back, writing a ‘0’ has no effect
Field Description
0
LPOCIF
LIN Transmitter Over-Current Interrupt Flag
LPOCIF is set to 1 when LPOC status bit changes. This flag can only be cleared by writing a 1. Writing a 0 has
no effect. If interrupt requests are enabled (LPOCIE= 1), LPOCIF causes an interrupt request.
0 No change in LPOC status bit.
1 LPOC status bit has changed.
Note: When entering standby mode, LPOCIF is not cleared.
The slew rate can be selected for EMC (Electromagnetic compatibility) optimized operation at 10.4kBit/s
and 20kBit/s as well as at fast baud rate (up to 250kBit/s) for test and programming. The slew rate can be
chosen with the bits LPSLR[1:0] in the LIN Slew Rate Register (LPSLR). The default slew rate
corresponds to 20kBit/s.
Generally, changing the slew rate has an immediate effect on the rising/falling edges of the LIN signal.
However, it is recommended to change the slew rate only in recessive state, and at least 2us before a falling
edge of TXD. If the slew rate is changed less than 2us before a falling edge of TXD, the slew rate change
may be effective only at the second next TXD falling edge.
MC9S12VR Family Reference Manual, Rev. 2.8
434 Freescale Semiconductor