DF2148BTE20 Renesas Electronics America, DF2148BTE20 Datasheet - Page 418

• Manufacturer Part Number: DF2148BTE20
• Description: IC H8S MCU FLASH 128K 100-QFP
• Manufacturer: Renesas Electronics America
• Series: H8® H8S/2100r

Specifications of DF2148BTE20

• Core Processor: H8S/2000
• Core Size: 16-Bit
• Speed: 20MHz
• Connectivity: I²C, IrDA, SCI, X-Bus
• Peripherals: PWM, WDT
• Number Of I /o: 74
• Program Memory Size: 128KB (128K x 8)
• Program Memory Type: FLASH
• Ram Size: 4K x 8
• Voltage - Supply (vcc/vdd): 4.5 V ~ 5.5 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: -
• Other names: HD64F2148BTE20; HD64F2148BTE20

Section 15 Serial Communication Interface (SCI and IrDA)
15.3.1
RSR is a shift register used to receive serial data that converts it into parallel data. When one
frame of data has been received, it is transferred to RDR automatically. RSR cannot be directly
accessed by the CPU.
15.3.2
RDR is an 8-bit register that stores receive data. When the SCI has received one frame of serial
data, it transfers the received serial data from RSR to RDR where it is stored. After this, RSR can
receive the next data. Since RSR and RDR function as a double buffer in this way, continuous
receive operations can be performed. After confirming that the RDRF bit in SSR is set to 1, read
RDR for only once. RDR cannot be written to by the CPU. RDR is initialized to H'00.
15.3.3
TDR is an 8-bit register that stores transmit data. When the SCI detects that TSR is empty, it
transfers the transmit data written in TDR to TSR and starts transmission. The double-buffered
structures of TDR and TSR enables continuous serial transmission. If the next transmit data has
already been written to TDR when one frame of data is transmitted, the SCI transfers the written
data to TSR to continue transmission. Although TDR can be read from or written to by the CPU at
all times, to achieve reliable serial transmission, write transmit data to TDR for only once after
confirming that the TDRE bit in SSR is set to 1. TDR is initialized to H'FF.
15.3.4
TSR is a shift register that transmits serial data. To perform serial data transmission, the SCI first
transfers transmit data from TDR to TSR, then sends the data to the TxD pin. TSR cannot be
directly accessed by the CPU.
Rev. 3.00 Mar 21, 2006 page 362 of 788
REJ09B0300-0300
Receive Shift Register (RSR)
Receive Data Register (RDR)
Transmit Data Register (TDR)
Transmit Shift Register (TSR)