MC68302EH16C Freescale Semiconductor, MC68302EH16C Datasheet - Page 417

• 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

With the above configuration, the data in the receive buffers will be as follows:
Four events in the SCCE2 event register will be set:
D.8.12 Special Uses of Transparent Mode
The following paragraphs discuss two special cases where transparent mode can be used
to extend the capabilities of the MC68302 UART mode.
D.8.12.1 5- OR 6-BIT UART. One special protocol of note that can be accomplished with
transparent mode is the building of a 5- or 6-bit UART. The UART on the SCCs offers 7- and
8-bit modes only.
A 5- or 6-bit UART can be accomplished with software and the transparent mode. Software
is responsible for inserting and deleting start and stop bits; the transparent mode provides
oversampling.
Select transparent mode for 8x the desired bit rate. For every bit of data to transmit, write a
byte of data to memory. A character will then be encoded as one byte of zeros for the start
bit, a byte of either zeros or ones for every bit in the character, and a byte of ones for each
stop bit. When there is no data to send, the transmitter will send out ones during the idle
period if the buffer had its L bit set.
Reception is more software intensive. The data is received at 8x the desired rate, and the
software must extract the start, stop, and character bits from the data stream. There is no
easy way to “byte align” the received data to byte boundaries in memory (as explained in
D.8.5 Transparent Mode with the NMSI Physical Interface) without some added external
hardware.
D.8.12.2 SYNCHRONOUS UART. A synchronous UART may also be built with transpar-
ent mode. As with a 5- or 6-bit UART, all data including start and stop bits must be placed
into the transmit buffer and the true data extracted from the raw transparent data that in-
cludes start and stop bits. (V.14 applications would also require the detection of deleted stop
bits.)
MOTOROLA
13. The final change is to set the ENT and ENR bits in the SCM2 register, causing the
—RX—One or more receive buffers have been used (in this case two).
—TX—One or more buffers have been transmitted (in this case one).
—BSY—Receive data was discarded due to lack of receive buffers (occurred because
—RCH—A word of data has been written to a receive buffer (occurred each time a word
Rx BD = $5000 $xxxx $xxxx $xxxx (This Rx BD is not yet available.)
transfers to begin.
SCM2 = $603F
Buffer1: $FF, data1, data2, ..., datae, dataf.
Buffer2: data10, data11, ..., data17, data18, (and then 7 $FF bytes).
the third Rx BD was not empty).
was written).
MC68302 USER’S MANUAL
MC68302 Applications
D-67