Chapter 11 Freescale’s Scalable Controller Area Network (S12MSCANV3)
S12ZVHY/S12ZVHL Family Reference Manual Rev. 1.05
Freescale Semiconductor
467
11.4.4.2
Special System Operating Modes
The MSCAN module behaves as described within this specification in all special system operating modes.
Write restrictions which exist on specific registers in normal modes are lifted for test purposes in special
modes.
11.4.4.3
Emulation Modes
In all emulation modes, the MSCAN module behaves just like in normal system operating modes as
described within this specification.
11.4.4.4
Listen-Only Mode
In an optional CAN bus monitoring mode (listen-only), the CAN node is able to receive valid data frames
and valid remote frames, but it sends only “recessive” bits on the CAN bus. In addition, it cannot start a
transmission.
If the MAC sub-layer is required to send a “dominant” bit (ACK bit, overload flag, or active error flag),
the bit is rerouted internally so that the MAC sub-layer monitors this “dominant” bit, although the CAN
bus may remain in recessive state externally.
11.4.4.5
MSCAN Initialization Mode
The MSCAN enters initialization mode when it is enabled (CANE=1).
When entering initialization mode during operation, any on-going transmission or reception is
immediately aborted and synchronization to the CAN bus is lost, potentially causing CAN protocol
violations. To protect the CAN bus system from fatal consequences of violations, the MSCAN
immediately drives TXCAN into a recessive state.
NOTE
The user is responsible for ensuring that the MSCAN is not active when
initialization mode is entered. The recommended procedure is to bring the
MSCAN into sleep mode (SLPRQ = 1 and SLPAK = 1) before setting the
INITRQ bit in the CANCTL0 register. Otherwise, the abort of an on-going
message can cause an error condition and can impact other CAN bus
devices.
In initialization mode, the MSCAN is stopped. However, interface registers remain accessible. This mode
is used to reset the CANCTL0, CANRFLG, CANRIER, CANTFLG, CANTIER, CANTARQ, CANTAAK,
and CANTBSEL registers to their default values. In addition, the MSCAN enables the configuration of the
CANBTR0, CANBTR1 bit timing registers; CANIDAC; and the CANIDAR, CANIDMR message filters.
See
Section 11.3.2.1, “MSCAN Control Register 0 (CANCTL0)
,” for a detailed description of the
initialization mode.
Содержание MC9S12ZVHL32
Страница 21: ...S12ZVHY S12ZVHL Family Reference Manual Rev 1 05 Freescale Semiconductor 21 PAGE INTENTIONALLY LEFT BLANK...
Страница 22: ...S12ZVHY S12ZVHL Family Reference Manual Rev 1 05 22 Freescale Semiconductor PAGE INTENTIONALLY LEFT BLANK...
Страница 686: ...Chapter 20 ECC Generation module SRAM_ECCV1 S12ZVHY S12ZVHL Family Reference Manual Rev 1 05 686 Freescale Semiconductor...
Страница 752: ...Chapter 22 Supply Voltage Sensor BATSV2 S12ZVHY S12ZVHL Family Reference Manual Rev 1 05 752 Freescale Semiconductor...
Страница 774: ...Chapter 23 LIN Physical Layer S12LINPHYV2 S12ZVHY S12ZVHL Family Reference Manual Rev 1 05 774 Freescale Semiconductor...
Страница 788: ...Appendix A MCU Electrical Specifications S12ZVHY S12ZVHL Family Reference Manual Rev 1 05 788 Freescale Semiconductor...
Страница 794: ...Appendix B ADC Electricals S12ZVHY S12ZVHL Family Reference Manual Rev 1 05 794 Freescale Semiconductor...
Страница 798: ...Appendix D IRC Electrical Specifications S12ZVHY S12ZVHL Family Reference Manual Rev 1 05 798 Freescale Semiconductor...
Страница 802: ...Appendix F MSCAN Electrical Specifications S12ZVHY S12ZVHL Family Reference Manual Rev 1 05 802 Freescale Semiconductor...
Страница 806: ...Appendix G NVM Electrical Parameters S12ZVHY S12ZVHL Family Reference Manual Rev 1 05 806 Freescale Semiconductor...
Страница 810: ...Appendix H BATS Electrical Specifications S12ZVHY S12ZVHL Family Reference Manual Rev 1 05 810 Freescale Semiconductor...
Страница 816: ...Appendix K OSC32K Electrical Specifications S12ZVHY S12ZVHL Family Reference Manual Rev 1 05 816 Freescale Semiconductor...
Страница 822: ...Appendix L SPI Electrical Specifications S12ZVHY S12ZVHL Family Reference Manual Rev 1 05 822 Freescale Semiconductor...
Страница 826: ...Appendix M LINPHY Electrical Specifications S12ZVHY S12ZVHL Family Reference Manual Rev 1 05 826 Freescale Semiconductor...
Страница 829: ...Appendix O Package Information S12ZVHY S12ZVHL Family Reference Manual Rev 1 05 830 Freescale Semiconductor O 1 144 LQFP...
Страница 830: ...Appendix O Package Information S12ZVHY S12ZVHL Family Reference Manual Rev 1 05 Freescale Semiconductor 831...
Страница 831: ...Appendix O Package Information S12ZVHY S12ZVHL Family Reference Manual Rev 1 05 832 Freescale Semiconductor...
Страница 832: ...Appendix O Package Information S12ZVHY S12ZVHL Family Reference Manual Rev 1 05 Freescale Semiconductor 833 O 2 100 LQFP...
Страница 833: ...Appendix O Package Information S12ZVHY S12ZVHL Family Reference Manual Rev 1 05 834 Freescale Semiconductor...
Страница 834: ...Appendix O Package Information S12ZVHY S12ZVHL Family Reference Manual Rev 1 05 Freescale Semiconductor 835...
Страница 835: ...Appendix O Package Information S12ZVHY S12ZVHL Family Reference Manual Rev 1 05 836 Freescale Semiconductor...