MC68302EH20C Freescale Semiconductor, MC68302EH20C Datasheet - Page 147

• Manufacturer Part Number: MC68302EH20C
• Description: IC MPU MULTI-PROTOCOL 132-PQFP
• Manufacturer: Freescale Semiconductor

Specifications of MC68302EH20C

• Processor Type: M683xx 32-Bit
• Speed: 20MHz
• Voltage: 5V
• Mounting Type: Surface Mount
• Package / Case: 132-MQFP, 132-PQFP
• Family Name: M68000
• Device Core: ColdFire
• Device Core Size: 32b
• Frequency (max): 20MHz
• 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: Compliant

crystal, an externally supplied UART clock on the TCLK or RCLK pins can be as high as
6.67 MHz, giving a maximum baud rate of 417 kbaud.
The baud rate using the baud rate generator is (System Clock or TIN1 clock)/(1 or 4)/(Clock
Divider + 1)/16. The baud rate using the baud rate generator with an externally supplied
clock to the TCLK or RCLK pins is always (TCLK or RCLK)/16.
Table 4-4 shows examples of typical bit rates of asynchronous communication and how to
obtain them with the baud rate generator using an internally supplied clock.
4.5.2.2 Synchronous Baud Rate Generator Examples
For synchronous communication (HDLC/SDLC, BISYNC, DDCMP, Transparent, and
V.110), the internal clock is identical to the baud rate output. To obtain the desired rate, the
user selects the appropriate system clock according to the following equation:
For example, to get the data rate of 64 kbps, the system clock can be 15.36 MHz, DIV4 = 0,
and the Clock Divider = 239. Of course, a 64 kbps rate provided externally on the TCLK or
RCLK pins could also be used.
4.5.3 SCC Mode Register (SCM)
Each SCC has a mode register. The functions of bits 5–0 are common to each protocol. The
function of the specific mode bits varies according to the protocol selected by the MODE1–
MODE0 bits. They are described in the relevant sections for each protocol type. Each SCM
is a 16-bit, memory-mapped, read-write register. The SCMs are cleared by reset.
DIAG1–DIAG0—Diagnostic Mode
MOTOROLA
Baud Rates
15
19200
38400
00 = Normal operation (CTS, CD lines under automatic control)
1200
2400
4800
9600
150
300
600
Baud rate = (System Clock or TIN1 Clock)/(Clock Divider + 1)/(1 or 4) according
In this mode, the CTS and CD lines are monitored by the SCC controller. The
SCC controller uses these lines to automatically enable/disable reception and
transmission.
Table 4-4. Typical Bit Rates of Asynchronous Communication
DIV4
1
1
0
0
0
0
0
0
0
SPECIFIC MODE BITS
1599
1599
DIV
799
799
399
199
99
49
24
15.36
Frequency
Actual
19200
38400
1200
2400
4800
9600
150
300
600
MC68302 USER’S MANUAL
to the DIV4 bit
DIV4
1
1
0
0
0
0
0
0
0
1666
1666
DIV
832
832
416
207
103
51
25
16.0
6
DIAG1
Frequency
38461.53
5
19230.8
Actual
1200.48
2398.08
4807.69
9615.34
149.97
300.12
599.88
DIAG0
Communications Processor (CP)
4
DIV4
ENR
1
1
0
0
0
0
0
0
0
3
ENT
1735
1735
DIV
867
867
433
216
108
2
16.667
53
26
MODE1
19290.5
38581.0
Frequency
1
1200.1
2400.2
4800.4
9556.76
Actual
150.01
300.02
600.05
MODE0
4-27
0