DF2117VT20V Renesas Electronics America, DF2117VT20V Datasheet - Page 268

• Manufacturer Part Number: DF2117VT20V
• Description: MCU 16BIT FLASH 3V 160K 144-TQFP
• Manufacturer: Renesas Electronics America
• Series: H8® H8S/2100r

Specifications of DF2117VT20V

• Core Processor: H8S/2600
• Core Size: 16-Bit
• Speed: 20MHz
• Connectivity: FIFO, I²C, LPC, SCI, SmartCard
• Peripherals: POR, PWM, WDT
• Number Of I /o: 112
• Program Memory Size: 160KB (160K x 8)
• Program Memory Type: FLASH
• Ram Size: 8K x 8
• Voltage - Supply (vcc/vdd): 3 V ~ 3.6 V
• Data Converters: A/D 16x10b
• Oscillator Type: External
• Operating Temperature: -20°C ~ 75°C
• Package / Case: 144-TQFP, 144-VQFP
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Eeprom Size: -

9.4
DACNT, DADRA, and DADRB are 16-bit registers. The data bus linking the bus master and the
on-chip peripheral modules, however, is only 8 bits wide. When the bus master accesses these
registers, it therefore uses an 8-bit temporary register (TEMP).
These registers are written to and read from as follows.
• Write
• Read
These registers should always be accessed 16 bits at a time with a MOV instruction, and the upper
byte should always be accessed before the lower byte. Correct data will not be transferred if only
the upper byte or only the lower byte is accessed. Also note that a bit manipulation instruction
cannot be used to access these registers.
Example 1: Write to DACNT
Example 2: Read DADRA
Rev. 2.00 Sep. 28, 2009 Page 226 of 994
REJ09B0452-0200
MOV.W R0, @DACNT
MOV.W @DADRA, R0
When the upper byte is written to, the upper-byte write data is stored in TEMP. Next, when the
lower byte is written to, the lower-byte write data and TEMP value are combined, and the
combined 16-bit value is written in the register.
When the upper byte is read from, 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 from, the lower-
byte value in TEMP is transferred to the CPU.
Bus Master Interface
; Write R0 contents to DACNT
; Copy contents of DADRA to R0