D12321VF25V Renesas Electronics America, D12321VF25V Datasheet - Page 226

• Manufacturer Part Number: D12321VF25V
• Description: IC H8S/2300 MCU ROMLESS 128QFP
• Manufacturer: Renesas Electronics America
• Series: H8® H8S/2300r

Specifications of D12321VF25V

• Core Processor: H8S/2000
• Core Size: 16-Bit
• Speed: 25MHz
• Connectivity: SCI, SmartCard
• Peripherals: POR, PWM, WDT
• Number Of I /o: 86
• Program Memory Type: ROMless
• Ram Size: 4K x 8
• Voltage - Supply (vcc/vdd): 2.7 V ~ 3.6 V
• Data Converters: A/D 8x10b; D/A 2x8b
• Oscillator Type: Internal
• Operating Temperature: -20°C ~ 75°C
• Package / Case: 128-QFP
• For Use With: EDK2329 - DEV EVALUATION KIT H8S/2329
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Eeprom Size: -
• Program Memory Size: -

Section 6 Bus Controller
•
Rev.6.00 Sep. 27, 2007 Page 194 of 1268
REJ09B0220-0600
To select RAS up mode, clear the RCDM bit in MCR to 0. Each time access to DRAM space
is interrupted and another space is accessed, the RAS signal goes high again. Burst operation is
only performed if DRAM space is continuous. Figure 6.22 shows an example of the timing in
RAS up mode.
In the case of burst ROM space access, the RAS signal is not restored to the high level.
RAS up mode
CAS, LCAS
Note: n = 2 to 5
CSn (RAS)
D
A
15
23
to D
to A
φ
0
0
Figure 6.22 Example of Operation Timing in RAS Up Mode
T
p
DRAM access
T
r
T
c1
T
c2
DRAM access
T
c1
T
c2
External space
T
1
access
T
2