DF2148RTE20IV Renesas Electronics America, DF2148RTE20IV Datasheet - Page 669

• Manufacturer Part Number: DF2148RTE20IV
• Description: MCU 5V 128K I-TEMP,PB-FREE, 100-
• Manufacturer: Renesas Electronics America
• Series: H8® H8S/2100r

Specifications of DF2148RTE20IV

• Core Processor: H8S/2000
• Core Size: 16-Bit
• Speed: 20MHz
• Connectivity: Host Interface, I²C, IrDA, SCI
• Peripherals: POR, 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 V ~ 5.5 V
• Data Converters: A/D 8x10b; D/A 2x8b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 100-TQFP, 100-VQFP
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Eeprom Size: -

20.3
ADDRA to ADDRD are 16-bit registers, but the data bus to the bus master is only 8 bits wide.
Therefore, in accesses by the bus master, the upper byte is accessed directly, but the lower byte is
accessed via a temporary register (TEMP).
A data read from ADDR is performed as follows. When the upper byte is read, the upper byte
value is transferred to the CPU and the lower byte value is transferred to TEMP. Next, when the
lower byte is read, the TEMP contents are transferred to the CPU.
When reading ADDR, always read the upper byte before the lower byte. It is possible to read only
the upper byte, but if only the lower byte is read, incorrect data may be obtained.
Figure 20.2 shows the data flow for ADDR access.
Interface to Bus Master
Bus master
(H'AA)
Bus master
(H'40)
Lower byte read
Upper byte read
Figure 20.2 ADDR Access Operation (Reading H'AA40)
Bus interface
Bus interface
ADDRnH
ADDRnH
(H'AA)
(H'AA)
Rev. 4.00 Sep 27, 2006 page 623 of 1130
ADDRnL
ADDRnL
(H'40)
(H'40)
TEMP
TEMP
(H'40)
(H'40)
Module data bus
Module data bus
Section 20 A/D Converter
(n = A to D)
(n = A to D)
REJ09B0327-0400