HD6417708SF60V Renesas Electronics America, HD6417708SF60V Datasheet - Page 118

• Manufacturer Part Number: HD6417708SF60V
• Description: IC SUPERH MPU ROMLESS 208LQFP
• Manufacturer: Renesas Electronics America
• Series: SuperH® SH7700r

Specifications of HD6417708SF60V

• Core Processor: SH-2
• Core Size: 32-Bit
• Speed: 60MHz
• Connectivity: EBI/EMI, SCI, SmartCard
• Peripherals: POR, WDT
• Number Of I /o: 8
• Program Memory Type: ROMless
• Voltage - Supply (vcc/vdd): 3 V ~ 3.6 V
• Oscillator Type: External
• Operating Temperature: -20°C ~ 75°C
• Package / Case: 208-LQFP
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Eeprom Size: -
• Ram Size: -
• Program Memory Size: -
• Data Converters: -

Address Array: The V bit indicates whether the entry data is valid. When the V bit is 1, data is
valid; when 0, data is not valid. The U bit indicates whether the entry has been written to in write-
back mode. When the U bit is 1, the entry has been written to; when 0, it has not. The address tag
holds the physical address used in the external memory access. It is composed of 22 bits (address
bits 31–10) used for comparison during cache searches.
In the SH7708 Series, the top three of the 32 physical address bits are used as shadow bits (see
section 10), and therefore in a normal replace operation the top three bits of the vector address are
cleared to 0.
The V and U bits are initialized to 0 by a power-on reset, but are not initialized by a manual reset.
The tag address is not initialized by either a power-on or manual reset.
Data Array: Holds a 16-byte instruction or data. Entries are registered in the cache in line units
(16 bytes). The data array is not initialized by a power-on or manual reset.
LRU: With the 4-way set associative system, up to four instructions or data with the same entry
address (address bits 10–4) can be registered in the cache. When an entry is registered, the LRU
shows which of the four ways it is recorded in. There are six LRU bits, controlled by hardware. A
least-recently-used (LRU) algorithm is used to select the way.
In normal mode, four ways are used as cache and six LRU bits indicate the way to be replaced
(table 5.2). If a bit pattern other than those listed in table 5.2 is set in the LRU bits by software, the
cache will not function correctly. When modifying the LRU bits by software, set one of the
patterns listed in table 5.2.
98
Entry 127
Entry 0
Entry 1
Address array (ways 0–3)
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•
•
•
24 (1 + 1 + 22) bits
V U
Address
Figure 5.1 Cache Structure
127
0
1
•
•
•
•
LW0–LW3: Longword data 0–3
LW0
Data array (ways 0–3)
128 (32
LW1
LW2
4) bits
LW3
127
LRU section
0
1
•
•
•
•
6 bits