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S912XET256J2MAL Datasheet, PDF (622/1324 Pages) Freescale Semiconductor, Inc – MC9S12XEP100 Reference Manual Covers MC9S12XE Family | |||
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Chapter 16 Freescaleâs Scalable Controller Area Network (S12MSCANV3)
1. Read: Anytime
Write: Anytime when not in initialization mode
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).
Table 16-14. 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
request.
16.3.2.9 MSCAN Transmitter Message Abort Request Register (CANTARQ)
The CANTARQ register allows abort request of queued messages as described below.
Module Base + 0x0008
Access: User read/write(1)
7
6
5
4
3
2
1
R
0
0
0
0
0
ABTRQ2 ABTRQ1
W
Reset:
0
0
0
0
0
0
0
= Unimplemented
Figure 16-12. MSCAN Transmitter Message Abort Request Register (CANTARQ)
1. Read: Anytime
Write: Anytime when not in initialization mode
0
ABTRQ0
0
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).
Table 16-15. CANTARQ Register Field Descriptions
Field
Description
2-0
Abort Request â The CPU sets the ABTRQx bit to request that a scheduled message buffer (TXEx = 0) be
ABTRQ[2:0] 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
Section 16.3.2.7, âMSCAN Transmitter Flag Register (CANTFLG)â) and abort acknowledge ï¬ags (ABTAK, see
Section 16.3.2.10, âMSCAN Transmitter Message Abort Acknowledge Register (CANTAAK)â) are set and a
transmit interrupt occurs if enabled. The CPU cannot reset ABTRQx. ABTRQx is reset whenever the associated
TXE ï¬ag is set.
0 No abort request
1 Abort request pending
MC9S12XE-Family Reference Manual Rev. 1.25
622
Freescale Semiconductor
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