HD64F3672FXV Renesas Electronics America, HD64F3672FXV Datasheet - Page 228

• Manufacturer Part Number: HD64F3672FXV
• Description: IC H8/3672 MCU FLASH 48LQFP
• Manufacturer: Renesas Electronics America
• Series: H8® H8/300H Tinyr

Specifications of HD64F3672FXV

• Core Processor: H8/300H
• Core Size: 16-Bit
• Speed: 16MHz
• Connectivity: SCI
• Peripherals: PWM, WDT
• Number Of I /o: 26
• Program Memory Size: 16KB (16K x 8)
• Program Memory Type: FLASH
• Ram Size: 2K x 8
• Voltage - Supply (vcc/vdd): 3 V ~ 5.5 V
• Data Converters: A/D 4x10b
• Oscillator Type: Internal
• Operating Temperature: -20°C ~ 75°C
• Package / Case: 48-LQFP
• For Use With: R0K436079S000BE - KIT DEV FOR H8/36079 W/COMPILER
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Eeprom Size: -

Section 13 Serial Communication Interface 3 (SCI3)
13.8.4
In asynchronous mode, the SCI3 operates on a basic clock with a frequency of 16 times the
transfer rate. In reception, the SCI3 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 13.19.
Thus, the reception margin in asynchronous mode is given by formula (1) below.
M = (0.5 –
Where N : Ratio of bit rate to clock (N = 16)
Assuming values of F (absolute value of clock rate deviation) = 0 and D (clock duty) = 0.5 in
formula (1), the reception margin can be given by the formula.
M = {0.5 – 1/(2 16)} 100 [%] = 46.875%
However, this is only the computed value, and a margin of 20% to 30% should be allowed for in
system design.
Rev.4.00 Nov. 02, 2005 Page 202 of 304
REJ09B0143-0400
D : Clock duty (D = 0.5 to 1.0)
L : Frame length (L = 9 to 12)
F : Absolute value of clock rate deviation
Receive Data Sampling Timing and Reception Margin in Asynchronous Mode
Internal basic
clock
Receive data
(RxD)
Synchronization
sampling timing
Data sampling
timing
2N
Figure 13.19 Receive Data Sampling Timing in Asynchronous Mode
1
) –
D – 0.5
N
0
– (L – 0.5) F
8 clocks
Start bit
16 clocks
7
100(%)
15 0
D0
7
... Formula (1)
15 0
D1