HD6417712BPV Renesas Electronics America, HD6417712BPV Datasheet - Page 181

• 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: -

3.5.11
The S bit in SR is effective for any arithmetic operations executed in the DSP unit, including the
SH's standard multiply and MAC operations. The S bit in SR is used as the overflow protection
enable bit. The arithmetic operation overflows when the operation result exceeds the range of
two’s complement representation without guard-bit parts. Table 3.31 shows the definition of
overflow protection for fixed-point arithmetic operations, including fixed-point signed by signed
multiplication described in section 3.5.7, Fixed-Point Multiply Operation. Table 3.32 shows the
definition of overflow protection for integer arithmetic operations. The lower word of the
saturation value of the integer arithmetic operation is don’t care. Lower word value cannot be
guaranteed.
When the overflow protection is effective, overflow never occurs. So, the V bit is cleared, and the
DC bit is also cleared when the overflow mode is selected by the CS[2:0] bits.
Table 3.31 Definition of Overflow Protection for Fixed-Point Arithmetic Operations
Table 3.32 Definition of Overflow Protection for Integer Arithmetic Operations
Note:
Sign
Positive
Negative
Sign
Positive
Negative
*
Overflow Protection
means don't care.
Overflow Condition
Result > 1 – 2
Result < –1
Overflow Condition
Result > 2
Result < –2
15
15
– 1
–31
Fixed Value
1 – 2
–1
Fixed Value
2
–2
15
15
– 1
–31
Rev. 1.00 Dec. 27, 2005 Page 137 of 1044
Section 3 DSP Operating Unit
Hex Representation
00 7FFF FFFF
FF 8000 0000
Hex Representation
00 7FFF ****
FF 8000 ****
REJ09B0269-0100