XC908AS60ACFU Motorola Semiconductor Products, XC908AS60ACFU Datasheet - Page 422

• Manufacturer Part Number: XC908AS60ACFU
• Description: MC68HC908AZ60A, MC68HC908AS60A Hcmos Microcontroller Unit Technical Data
• Manufacturer: Motorola Semiconductor Products

MSCAN Controller (MSCAN08)
Technical Data
422
NOTE:
NOTE:
ABTAK2–ABTAK0 — Abort Acknowledge
TXE2–TXE0 — Transmitter Empty
To ensure data integrity, no registers of the transmit buffers should be
written to while the associated TXE flag is cleared.
The CTFLG register is held in the reset state when the SFTRES bit in
CMCR0 is set.
This flag acknowledges that a message has been aborted due to a
pending abort request from the CPU. After a particular message
buffer has been flagged empty, this flag can be used by the
application software to identify whether the message has been
aborted successfully or has been sent. The ABTAKx flag is cleared
implicitly whenever the corresponding TXE flag is cleared.
This flag indicates that the associated transmit message buffer is
empty, thus not scheduled for transmission. The CPU must
handshake (clear) the flag after a message has been set up in the
transmit buffer and is due for transmission. The MSCAN08 sets the
flag after the message has been sent successfully. The flag is also set
by the MSCAN08 when the transmission request was successfully
aborted due to a pending abort request (see
Priority Registers
pending while this flag is set.
Clearing a TXEx flag also clears the corresponding ABTAKx flag
(ABTAK, see above). When a TXEx flag is set, the corresponding
ABTRQx bit (ABTRQ, see
on page 423) is cleared.
1 = The message has been aborted.
0 = The message has not been aborted, thus has been sent out.
1 = The associated message buffer is empty (not scheduled).
0 = The associated message buffer is full (loaded with a message
due for transmission).
MSCAN Controller (MSCAN08)
on page 408). If not masked, a receive interrupt is
MSCAN08 Transmitter Control Register
MC68HC908AZ60A — Rev 2.0
Transmit Buffer
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