DF3048BVX25V Renesas Electronics America, DF3048BVX25V Datasheet - Page 213

• Manufacturer Part Number: DF3048BVX25V
• Description: MCU 3/5V 128K PB-FREE 100-TQFP
• Manufacturer: Renesas Electronics America
• Series: H8® H8/300Hr

Specifications of DF3048BVX25V

• Core Processor: H8/300H
• Core Size: 16-Bit
• Speed: 25MHz
• Connectivity: SCI, SmartCard
• Peripherals: DMA, PWM, WDT
• Number Of I /o: 70
• Program Memory Size: 128KB (128K x 8)
• Program Memory Type: FLASH
• Ram Size: 4K 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: Lead free / RoHS Compliant
• Eeprom Size: -

7.3.3
Refresh Request Interval and Refresh Cycle Execution
The refresh request interval is determined as in a DRAM interface, by the settings of RTCOR and
bits CKS2 to CKS0 in RTMCSR. The numbers of states required for pseudo-static RAM
read/write cycles and refresh cycles are the same as for DRAM (see table 7.4). The state
transitions are as shown in figure 7.3.
Figure 7.14 Setup Procedure for Multiple 2CAS
Pseudo-Static RAM Refresh Control
Address and 9-Bit Column Address (16-Mbyte Mode)
Set bits CKS2 to CKS0 in RTMCSR
Set P8 DDR to 1 for CS output
Wait for DRAM to be initialized
Set area 3 for 16-bit access
DRAM can be accessed
Write H'3F in RFSHCR
1
Set RTCOR
CAS
CAS
CAS 4-Mbit DRAM Chips with 9-Bit Row
Rev. 3.00 Sep 27, 2006 page 185 of 872
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Section 7 Refresh Controller
REJ09B0325-0300