HD64F7047FW40V Renesas Electronics America, HD64F7047FW40V Datasheet - Page 395

• Manufacturer Part Number: HD64F7047FW40V
• Description: MCU 5V 256K I-TEMP,PB-FREE 100-Q
• Manufacturer: Renesas Electronics America
• Series: SuperH® SH7047r

Specifications of HD64F7047FW40V

• Core Processor: SH-2
• Core Size: 32-Bit
• Speed: 40MHz
• Connectivity: CAN, SCI
• Peripherals: POR, PWM, WDT
• Number Of I /o: 53
• Program Memory Size: 256KB (256K x 8)
• Program Memory Type: FLASH
• Ram Size: 12K x 8
• Voltage - Supply (vcc/vdd): 4.5 V ~ 5.5 V
• Data Converters: A/D 16x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 100-QFP
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Eeprom Size: -

12.4.2
In asynchronous mode, the SCI operates on a basic clock with a frequency of 16 times the bit rate.
In reception, the SCI samples the falling edge of the start bit using the basic clock, and performs
internal synchronization. Receive data is latched internally at the rising edge of the 8th pulse of
the basic clock as shown in figure 12.3. Thus the reception margin in asynchronous mode is given
by formula (1) below.
Where M: Reception margin (%)
Assuming values of F = 0 and D = 0.5 in formula (1), a reception margin is given by formula
below.
However, this is only the computed value, and a margin of 20% to 30% should be allowed in
system design.
Internal basic
clock
Receive data
(RxD)
Synchronization
sampling timing
Data sampling
timing
M =
N: Ratio of bit rate to clock (N = 16)
D: Clock duty (D = 0 to 1.0)
L: Frame length (L = 9 to 12)
F: Absolute value of clock rate deviation
M = {0.5 – 1/(2 × 16)} × 100 [%] = 46.875%
Receive Data Sampling Timing and Reception Margin in Asynchronous Mode
Figure 12.3 Receive Data Sampling Timing in Asynchronous Mode
0.5 –
0
2N
1
8 clocks
Start bit
–
(D – 0.5)
N
16 clocks
7
– (L – 0.5) F
× 100%
15 0
........................... Formula (1)
D0
Rev. 2.00, 09/04, page 353 of 720
7
15 0
D1