MC68376BAMFT20 Freescale Semiconductor, MC68376BAMFT20 Datasheet - Page 171

• Manufacturer Part Number: MC68376BAMFT20
• Manufacturer: Freescale Semiconductor

Specifications of MC68376BAMFT20

• Cpu Family: 68K/M683xx
• Device Core: ColdFire
• Device Core Size: 32b
• Frequency (max): 20MHz
• Interface Type: QSPI/SCI
• Program Memory Type: ROM
• Program Memory Size: 8KB
• Total Internal Ram Size: 7.5KB
• # I/os (max): 18
• Number Of Timers - General Purpose: 2
• Operating Supply Voltage (typ): 5V
• Operating Supply Voltage (max): 5.25V
• Operating Supply Voltage (min): 4.75V
• On-chip Adc: 16-chx10-bit
• Instruction Set Architecture: RISC
• Operating Temp Range: -40C to 125C
• Operating Temperature Classification: Automotive
• Mounting: Surface Mount
• Pin Count: 160
• Package Type: PQFP
• Lead Free Status / Rohs Status: Not Compliant

9.4 Serial Communication Interface
9.4.1 SCI Registers
9.4.1.1 Control Registers
MC68336/376
USER’S MANUAL
To configure a peripheral chip-select, set the appropriate bit in PQSPAR, then config-
ure the chip-select pin as an output by setting the appropriate bit in DDRQS. The value
of the bit in PORTQS that corresponds to the chip-select pin determines the base state
of the chip-select signal. If base state is zero, chip-select assertion must be active high
(PCS bit in command RAM must be set); if base state is one, assertion must be active
low (PCS bit in command RAM must be cleared). PORTQS bits are cleared during re-
set. If no new data is written to PORTQS before pin assignment and configuration as
an output, base state of chip-select signals is zero and chip-select pins are configured
for active-high operation.
The serial communication interface (SCI) communicates with external devices through
an asynchronous serial bus. The SCI uses a standard non-return to zero (NRZ) trans-
mission format. The SCI is fully compatible with other Motorola SCI systems, such as
those on M68HC11 and M68HC05 devices. Figure 9-10 is a block diagram of the SCI
transmitter. Figure 9-11 is a block diagram of the SCI receiver.
The SCI programming model includes the QSM global and pin control registers, and
four SCI registers. There are two SCI control registers (SCCR0 and SCCR1), one sta-
tus register (SCSR), and one data register (SCDR). Refer to D.6 Queued Serial Mod-
ule for register bit and field definitions.
SCCR0 contains the baud rate selection field. Baud rate must be set before the SCI is
enabled. This register can be read or written.
SCCR1 contains a number of SCI configuration parameters, including transmitter and
receiver enable bits, interrupt enable bits, and operating mode enable bits. This regis-
ter can be read or written at any time. The SCI can modify the RWU bit under certain
circumstances.
Changing the value of SCI control bits during a transfer may disrupt operation. Before
changing register values, allow the SCI to complete the current transfer, then disable
the receiver and transmitter.
QUEUED SERIAL MODULE
MOTOROLA
9-21