s908az32ag2cfue Freescale Semiconductor, Inc, s908az32ag2cfue Datasheet - Page 291

• Manufacturer Part Number: s908az32ag2cfue
• Description: M68hc08 Microcontrollers 8-bit Microcontroller
• Manufacturer: Freescale Semiconductor, Inc

24.13.8 MSCAN08 Transmitter Control Register
ABTRQ2–ABTRQ0 — Abort Request
TXEIE2–TXEIE0 — Transmitter Empty Interrupt Enable
Freescale Semiconductor
The CPU sets an ABTRQx bit to request that an already scheduled message buffer (TXE = 0) be
aborted. The MSCAN08 will grant 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 and the abort acknowledge flag (ABTAK) (see
Register) will be set and an TXE interrupt is generated if enabled. The CPU cannot reset ABTRQx.
ABTRQx is cleared implicitly whenever the associated TXE flag is set.
1 = Abort request pending
0 = No abort request
1 = A transmitter empty (transmit buffer available for transmission) event results in a transmitter
0 = No interrupt is generated from this event.
empty interrupt.
Address:
The software must not clear one or more of the TXE flags in CTFLG and
simultaneously set the respective ABTRQ bit(s).
The CTCR register is held in the reset state when the SFTRES bit in
CMCR0 is set.
Reset:
Read:
Write:
$0507
Bit 7
0
0
Figure 24-22. Transmitter Control Register (CTCR)
= Unimplemented
ABTRQ2
6
0
MC68HC908AZ32A Data Sheet, Rev. 2
ABTRQ1
5
0
NOTE
NOTE
ABTRQ0
4
0
3
0
0
24.13.7 MSCAN08 Transmitter Flag
Programmer’s Model of Control Registers
TXEIE2
2
0
TXEIE1
1
0
TXEIE0
Bit 0
0
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