MC68302EH16C Freescale Semiconductor, MC68302EH16C Datasheet - Page 225

• Manufacturer Part Number: MC68302EH16C
• Description: IC MPU MULTI-PROTOCOL 132-PQFP
• Manufacturer: Freescale Semiconductor

Specifications of MC68302EH16C

• Processor Type: M683xx 32-Bit
• Speed: 16MHz
• Voltage: 5V
• Mounting Type: Surface Mount
• Package / Case: 132-MQFP, 132-PQFP
• Controller Family/series: 68K
• Core Size: 32 Bit
• Ram Memory Size: 1152Byte
• Cpu Speed: 16MHz
• No. Of Timers: 3
• Embedded Interface Type: SCP, TDM
• Digital Ic Case Style: PQFP
• Rohs Compliant: Yes
• Family Name: M68000
• Device Core: ColdFire
• Device Core Size: 32b
• Frequency (max): 16MHz
• Instruction Set Architecture: RISC
• Supply Voltage 1 (typ): 5V
• Operating Temp Range: 0C to 70C
• Operating Temperature Classification: Commercial
• Mounting: Surface Mount
• Pin Count: 132
• Package Type: PQFP
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Features: -
• Lead Free Status / Rohs Status: RoHS Compliant part Electrostatic Device

RESTART TRANSMIT Command
If the channel is being re-enabled, the RESTART TRANSMIT command must be used and
should be followed by the enabling of the transmitter in the SCC mode register.
ENTER HUNT MODE Command
4.5.14.6 DDCMP Control Character Recognition
The DDCMP controller can recognize three special control characters. These characters are
used to synchronize the message and allow the DDCMP controller to function in a DMA-con-
trolled environment.
DSYN1—DDCMP Sync Character Register
MOTOROLA
transmission, message transmission is aborted after the contents of the FIFO (up to three
bytes) are transmitted. The TBD# is not advanced. No new BD is accessed, and no new
messages are transmitted for this channel. Upon receipt of this command, the transmitter
aborts the message transmission (if currently transmitting) and then transmits SYN1–
SYN2 pairs or IDLEs as determined by the DDCMP mode register.
The STOP TRANSMIT command must be issued before the SCC mode register is used
to disable the transmitter if the transmitter is to be re-enabled at a later time.
The RESTART TRANSMIT command re-enables the transmission of characters on the
transmit channel. This command is expected by the DDCMP controller after a STOP
TRANSMIT command, after a STOP TRANSMIT command followed by the disabling of
the channel in its SCC mode register, or after a transmitter error (underrun or CTS lost
during data or maintenance message header fields). The DDCMP controller will resume
transmission from the current transmitter BD number (TBD#) in the channel's transmit BD
table.
After a hardware or software reset and the enabling of the channel in the SCC mode reg-
ister, the channel is in the receive enable mode and will use the first BD in the table.
The ENTER HUNT MODE command is used to force the DDCMP controller to abort re-
ception of the current message, generate an RBD interrupt (if enabled) as the buffer is
closed, and enter hunt mode. In hunt mode, the DDCMP controller continually scans the
input data stream for the SYN1–SYN2 sequence on synchronous links. Then for synchro-
nous or asynchronous links, the DDCMP controller scans the input bytes for the starting
byte of one of the messages. After receiving the command, the current receive buffer is
closed, and the CRC is reset. Message reception continues using the next BD.
If an enabled receiver has been disabled (by clearing ENR in the SCC mode register), the
ENTER HUNT MODE command must be given to the channel before setting ENR again.
The 8-bit DSYN1 register should be written with the same value that was written in the
SYN1 byte of the data synchronization register (DSR). DSYN1 is a memory-mapped
read-write register.
For correct operation of DDCMP, DSYN1, SYN1, and SYN2
must be the same value.
MC68302 USER’S MANUAL
NOTE
Communications Processor (CP)
4-105