C517A Datasheet, PDF (38/72 Pages) Siemens Semiconductor Group – 8-Bit CMOS Microcontroller

C517A
Multiplication / Division Unit (MDU)
This on-chip arithmetic unit of the C517A provides fast 32-bit division, 16-bit multiplication as well
as shift and normalize features. All operations are unsigned integer operations. Table 6 describes
the five general operations the MDU is able to perform.
Table 6
MDU Operation Characteristics
Operation
Result
Remainder
Execution Time
32bit/16bit
16bit/16bit
16bit x 16bit
32-bit normalize
32-bit shift L/R
32bit
16bit
32bit
–
–
16bit
16bit
–
–
–
6
t 1)
CY
4
t 1)
CY
4
t 1)
CY
6
t 2)
CY
6
t 2)
CY
1) 1 t_CY = 12 t_CLCL= 1 machine cycle = 500 ns at 24 MHz oscillator frequency
2) The maximal shift speed is 6 shifts per machine cycle
The MDU consists of seven special function registers (MD0-MD5, ARCON) which are used as
operand, result, and control registers. The three operation phases are shown in figure 17.
Figure 17
Operating Phases of the MDU
Semiconductor Group
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