SH7604 Datasheet, PDF (308/633 Pages) Hitachi Semiconductor – Hardware Manual

10.2.6 Dividend Register L (DVDNTL)
Bit: 31
30
39
…
3
2
1
0
Bit name:
…
Initial value: —
—
—
…
—
—
—
—
R/W: R/W R/W R/W
…
R/W R/W R/W R/W
Dividend register L (DVDNTL) is a 32-bit read/write register in which the lower 32 bits of the
dividend used for 64-bit ÷ 32-bit division operations are written. When a value is set in this
register, the 64-bit ÷ 32-bit division operation begins. The value written in the DVDNT register
for 32-bit ÷ 32-bit division is also set in this register. When a 64-bit ÷ 32-bit division operation is
executed, the value set as the dividend is lost and the quotient written here at the end of the
operation. The contents of this register are undefined after a power-on reset or manual reset, in
standby mode, and during module standbys.
10.3 Operation
10.3.1 64-Bit ÷ 32-Bit Operations
64-bit ÷ 32-bit operations work as follows:
1. The 32-bit divisor is set in the divisor register (DVSR).
2. The 64-bit dividend is set in dividend registers H and L (DVDNTH and DVDNTL). First set
the value in DVDNTH. When a value is written to DVDNTL, the 64-bit ÷ 32-bit operation
begins.
3. This unit finishes a single operation in 39 cycles (starting from the setting of the value in
DVDNTL). When an overflow occurs, however, the operation ends in 6 cycles. See section
10.3.3, Handling of Overflows, for more information. Note that operation is signed.
4. After the operation, the 32-bit remainder is written to DVDNTH and the 32-bit quotient is
written to DVDNTL.
10.3.2 32-Bit ÷ 32-Bit Operations
32-bit ÷ 32-bit operations work as follows:
1. The 32-bit divisor is set in the divisor register (DVSR).
2. The 32-bit dividend is set in dividend register L (DVDNT) for 32-bit division. When a value is
written to DVDNT, the 32-bit ÷ 32-bit operation begins.
3. This unit finishes a single operation in 39 cycles (starting from the setting of the value in
DVDNT). When an overflow occurs, however, the operation ends in 6 cycles. See section
10.3.3, Handling of Overflows, for more information. Note that the operation is signed.
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