HD6417020SX20IV Renesas Electronics America, HD6417020SX20IV Datasheet - Page 160

• Manufacturer Part Number: HD6417020SX20IV
• Description: SH 1 CORE 32B MPU, 20MHZ/5V, 100
• Manufacturer: Renesas Electronics America
• Series: SuperH® SH7020r

Specifications of HD6417020SX20IV

• Core Processor: SH-1
• Core Size: 32-Bit
• Speed: 20MHz
• Connectivity: EBI/EMI, SCI
• Peripherals: DMA, POR, PWM, WDT
• Number Of I /o: 32
• Program Memory Type: ROMless
• Ram Size: 1K x 8
• Voltage - Supply (vcc/vdd): 4.5 V ~ 5.5 V
• 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: -
• Program Memory Size: -
• Data Converters: -

When the RW1 bit is set to 1, the number of wait states selected by CBR refresh wait state
insertion bits 1 and 0 (RLW1, RLW0) of the refresh control register (RCR) are inserted into the
CAS-before-RAS refresh cycle.
8.5.4
Byte Access Control
16-bit width and 18-bit width DRAMs require different types of byte control signals for access. By
setting the dual CAS signals/dual WE signals select bit (CW2) in the DCR, the BSC allows
selection of either the dual CAS signals or the dual WE signals system of control signals. When
16-bit space is being accessed and the CW2 bit is cleared to 0 for dual CAS signals, CASH,
CASL, and WRL signals are output; when CW2 is set to 1 for dual WE signals, the CASL, WRH,
and WRL signals are output. When accessing 8-bit space, WRL and CASL are output regardless
of the CW2 setting.
Figure 8.21 shows the control timing of the upper byte write cycle (short pitch) in 16-bit space.
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