HD6417751RF240V Renesas Electronics America, HD6417751RF240V Datasheet - Page 395

• Manufacturer Part Number: HD6417751RF240V
• Description: MPU 1.5/3.3V 0K PB-FREE 256-QFP
• Manufacturer: Renesas Electronics America
• Series: SuperH® SH7750r

Specifications of HD6417751RF240V

• Core Processor: SH-4
• Core Size: 32-Bit
• Speed: 240MHz
• Connectivity: EBI/EMI, FIFO, SCI, SmartCard
• Peripherals: DMA, POR, WDT
• Number Of I /o: 39
• Program Memory Type: ROMless
• Ram Size: 48K x 8
• Voltage - Supply (vcc/vdd): 1.4 V ~ 1.6 V
• Oscillator Type: External
• Operating Temperature: -20°C ~ 75°C
• Package / Case: 256-QFP Exposed Pad, 256-eQFP, 256-HQFP
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Eeprom Size: -
• Program Memory Size: -
• Data Converters: -

11.2
11.2.1
R64CNT is an 8-bit read-only register that indicates a state of 64 Hz to 1 Hz within the RTC
frequency divider.
If this register is read when a carry is generated from the 128 kHz frequency division stage, bit 7
(CF) in RTC control register 1 (RCR1) is set to 1, indicating the simultaneous occurrence of the
carry and the 64 Hz counter read. In this case, the read value is not valid, and so R64CNT must be
read again after first writing 0 to the CF bit in RCR1 to clear it.
When the RESET bit or ADJ bit in RTC control register 2 (RCR2) is set to 1, the RTC frequency
divider is initialized and R64CNT is initialized to H'00.
R64CNT is not initialized by a power-on or manual reset, or in standby mode.
Bit 7 is always read as 0 and cannot be modified.
Initial value:
R/W:
Register Descriptions
64 Hz Counter (R64CNT)
Bit:
—
R
7
0
Undefined Undefined Undefined Undefined Undefined Undefined Undefined
1 Hz
R
6
2 Hz
R
5
4 Hz
R
4
Rev.4.00 Oct. 10, 2008 Page 295 of 1122
8 Hz
R
3
16 Hz
R
11. Realtime Clock (RTC)
2
REJ09B0370-0400
32 Hz
R
1
64 Hz
R
0