HD64F3026X25 Renesas Electronics America, HD64F3026X25 Datasheet - Page 423

• Manufacturer Part Number: HD64F3026X25
• Description: MCU 3V 256K 100-TQFP
• Manufacturer: Renesas Electronics America
• Series: H8® H8/300Hr

Specifications of HD64F3026X25

• Core Processor: H8/300H
• Core Size: 16-Bit
• Speed: 25MHz
• Connectivity: SCI, SmartCard
• Peripherals: PWM, WDT
• Number Of I /o: 70
• Program Memory Size: 256KB (256K x 8)
• Program Memory Type: FLASH
• Ram Size: 8K x 8
• Voltage - Supply (vcc/vdd): 3 V ~ 3.6 V
• Data Converters: A/D 8x10b; D/A 2x8b
• Oscillator Type: Internal
• Operating Temperature: -20°C ~ 75°C
• Package / Case: 100-TQFP, 100-VQFP
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Eeprom Size: -

12.3.2
In asynchronous mode, each transmitted or received character begins with a start bit and ends with
one or two stop bits. Serial communication is synchronized one character at a time.
The transmitting and receiving sections of the SCI are independent, so full-duplex communication
is possible. The transmitter and the receiver are both double-buffered, so data can be written and
read while transmitting and receiving are in progress, enabling continuous transmitting and
receiving.
Figure 12.2 shows the general format of asynchronous serial communication. In asynchronous
serial communication the communication line is normally held in the mark (high) state. The SCI
monitors the line and starts serial communication when the line goes to the space (low) state,
indicating a start bit. One serial character consists of a start bit (low), data (LSB first), parity bit
(high or low), and one or two stop bits (high), in that order.
When receiving in asynchronous mode, the SCI synchronizes at the falling edge of the start bit.
The SCI samples each data bit on the eighth pulse of a clock with a frequency 16 times the bit rate.
Receive data is latched at the center of each bit.
Communication Formats
Table 12.10 shows the 12 communication formats that can be selected in asynchronous mode. The
format is selected by settings in SMR.
Serial
data
1
Operation in Asynchronous Mode
Start
bit
1 bit
0
(LSB)
Figure 12.2 Data Format in Asynchronous Communication
D0
(Example: 8-Bit Data with Parity and 2 Stop Bits)
D1
One unit of data (character or frame)
D2
Transmit or receive data
D3
7 or 8 bits
D4
D5
Section 12 Serial Communication Interface
Rev. 2.00 Sep 20, 2005 page 383 of 800
D6
(MSB)
D7
Parity
bit
1 bit,
none
0/1
or
Stop bit(s)
1 or 2 bits
REJ09B0260-0200
1
Idle (mark) state
1
1