MC68000 MOTOROLA [Motorola, Inc], MC68000 Datasheet - Page 231

• Manufacturer Part Number: MC68000
• Manufacturer: MOTOROLA [Motorola, Inc]

T2,T1—Message Type
Bits 7–6—Reserved for future use.
CF—CRC Follow Error
FR—Framing Error
PR—Parity Error
CR—Rx CRC Error
OV—Overrun
CD—Carrier Detect Lost
Data Length
MOTOROLA
The character following the CRC for this message was not one of SOH, ENQ, DLE, SYN,
or IDLE. The receiver then enters hunt mode.
A character with a framing error was received. The associated character may be found at
the last location in this buffer. A framing error is detected by the UART controller when no
stop bit is detected in the receive data string.
A character with a parity error was received. The associated character may be found at
the last location in this buffer.
A message with a CRC error was received in the header (CRC1) or data (CRC2) fields or
a control message (CRC3).
A receiver overrun occurred during message reception.
The CD signal was negated during message reception. This bit is valid only when working
in NMSI mode.
The data length is the number of octets that the DDCMP controller has written to this BD's
data buffer. It is written by the CP once as the BD is closed.
00 = Data message
01 = Control message
10 = Maintenance message
11 = Reserved
This error can occur only on asynchronous DDCMP links.
This error can occur only on asynchronous DDCMP links.
The actual buffer size should be greater than or equal to eight
(to ensure the header is received in one buffer).
MC68302 USER’S MANUAL
NOTE
NOTE
NOTE
Communications Processor (CP)
4-111