mc9s12vr48 Freescale Semiconductor, Inc, mc9s12vr48 Datasheet - Page 436

• Manufacturer Part Number: mc9s12vr48
• Description: S12 Microcontrollers
• Manufacturer: Freescale Semiconductor, Inc

LIN Physical Layer (S12LINPHYV1)
15.3.2.8
1
15.4
15.4.1
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
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.
436
Module Base + Address 0x0007
Read: Anytime
Write: Writing ‘1’ sets the flags back, writing a ‘0’ has no effect
LPOCIF
Reset
Field
0
W
R
Functional Description
General
Slew Rate Selection
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.
LIN Interrupt Flags Register (LPIF)
0
0
7
= Unimplemented
0
0
6
Figure 15-9. LIN Interrupt Flags Register (LPIF)
MC9S12VR Family Reference Manual,
Preliminary - Subject to Change Without Notice
Table 15-11. LPIF Fields Description
0
0
5
0
0
4
Description
0
0
3
Rev. 2.2
0
0
2
Access: User read/write
Freescale Semiconductor
0
0
1
LPOCIF
0
0
1