HD6417712BPV Renesas Electronics America, HD6417712BPV Datasheet - Page 239

• Manufacturer Part Number: HD6417712BPV
• Description: MPU 1.5/3.3V 0K PB-FREE 256-BGA
• Manufacturer: Renesas Electronics America
• Series: SuperH® SH Ethernetr

Specifications of HD6417712BPV

• Core Processor: SH-3 DSP
• Core Size: 32-Bit
• Speed: 200MHz
• Connectivity: EBI/EMI, Ethernet, FIFO, SCI, SIO
• Peripherals: DMA, POR, WDT
• Number Of I /o: 24
• Program Memory Type: ROMless
• Ram Size: 16K x 8
• Voltage - Supply (vcc/vdd): 1.4 V ~ 1.6 V
• Oscillator Type: External
• Operating Temperature: -20°C ~ 75°C
• Package / Case: 256-BGA
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Eeprom Size: -
• Program Memory Size: -
• Data Converters: -

5.3.2
The TLB uses a 4-way set associative scheme, so entries must be selected by index. VPN bits 16
to 12 are used as the index number regardless of the page size. The index number can be generated
in two different ways depending on the setting of the IX bit in MMUCR.
1. When IX = 0, VPN bits 16 to 12 alone are used as the index number
2. When IX = 1, VPN bits 16 to 12 are EX-ORed with ASID bits 4 to 0 to generate a 5-bit index
The first method is used to prevent lowered TLB efficiency that results when multiple processes
run simultaneously in the same virtual address space (multiple virtual memory) and a specific
entry is selected by indexing of each process. In single virtual memory mode (MMUCR.SV = 1),
IX bit should be set to 0. Figures 5.8 and 5.9 show the indexing schemes.
number
TLB Indexing
31
0
Virtual Address
31
VPN(31-17)
Index
17
VPN(11-10)
Address Array
Figure 5.8 TLB Indexing (IX = 1)
16
12
11
ASID(7-0)
0
Exclusive-OR
V
Way 0 to 3
PPN(28-10) PR(1-0) SZ C
PTEH Register
31
Section 5 Memory Management Unit (MMU)
Rev. 1.00 Dec. 27, 2005 Page 195 of 932
VPN
Data Array
ASID(4-0)
10
0
D SH
REJ09B0269-0100
7
ASID
0