Техническая Спецификация для Freescale Semiconductor Tower System Eval Kit for MC9S12GN32 TWR-S12GN32-KIT TWR-S12GN32-KIT
Модели
TWR-S12GN32-KIT
Freescale’s Scalable Controller Area Network (S12MSCANV3)
MC9S12G Family Reference Manual, Rev.1.23
Freescale Semiconductor
601
NOTE
The CANTIER register is held in the reset state when the initialization mode
is active (INITRQ = 1 and INITAK = 1). This register is writable when not
in initialization mode (INITRQ = 0 and INITAK = 0).
is active (INITRQ = 1 and INITAK = 1). This register is writable when not
in initialization mode (INITRQ = 0 and INITAK = 0).
18.3.2.9
MSCAN Transmitter Message Abort Request Register (CANTARQ)
The CANTARQ register allows abort request of queued messages as described below.
NOTE
The CANTARQ register is held in the reset state when the initialization
mode is active (INITRQ = 1 and INITAK = 1). This register is writable when
not in initialization mode (INITRQ = 0 and INITAK = 0).
mode is active (INITRQ = 1 and INITAK = 1). This register is writable when
not in initialization mode (INITRQ = 0 and INITAK = 0).
1
Read: Anytime
Write: Anytime when not in initialization mode
Write: Anytime when not in initialization mode
Table 18-14. CANTIER Register Field Descriptions
Field
Description
2-0
TXEIE[2:0]
Transmitter Empty Interrupt Enable
0 No interrupt request is generated from this event.
1 A transmitter empty (transmit buffer available for transmission) event causes a transmitter empty interrupt
0 No interrupt request is generated from this event.
1 A transmitter empty (transmit buffer available for transmission) event causes a transmitter empty interrupt
request.
Module Base + 0x0008
Access: User read/write
1
1
Read: Anytime
Write: Anytime when not in initialization mode
Write: Anytime when not in initialization mode
7
6
5
4
3
2
1
0
R
0
0
0
0
0
ABTRQ2
ABTRQ1
ABTRQ0
W
Reset:
0
0
0
0
0
0
0
0
= Unimplemented
Figure 18-12. MSCAN Transmitter Message Abort Request Register (CANTARQ)
Table 18-15. CANTARQ Register Field Descriptions
Field
Description
2-0
ABTRQ[2:0]
Abort Request — The CPU sets the ABTRQx bit to request that a scheduled message buffer (TXEx = 0) be
aborted. The MSCAN grants the request if the message has not already started transmission, or if the
transmission is not successful (lost arbitration or error). When a message is aborted, the associated TXE (see
aborted. The MSCAN grants the request if the message has not already started transmission, or if the
transmission is not successful (lost arbitration or error). When a message is aborted, the associated TXE (see
”) and abort acknowledge flags (ABTAK, see
transmit interrupt occurs if enabled. The CPU cannot reset ABTRQx. ABTRQx is reset whenever the associated
TXE flag is set.
0 No abort request
1 Abort request pending
TXE flag is set.
0 No abort request
1 Abort request pending