PIC18F452-I/L Microchip Technology Inc., PIC18F452-I/L Datasheet - Page 73
PIC18F452-I/L
Manufacturer Part Number
PIC18F452-I/L
Description
44 PIN, 32 KB FLASH, 1536 RAM, 34 I/O
Manufacturer
Microchip Technology Inc.
Datasheet
1.PIC18F452-IL.pdf
(332 pages)
Specifications of PIC18F452-I/L
A/d Inputs
8-Channel, 10-Bit
Comparators
2
Cpu Speed
10 MIPS
Eeprom Memory
256 Bytes
Input Output
36
Interface
I2C/SPI/USART
Memory Type
Flash
Number Of Bits
8
Package Type
44-pin PLCC
Programmable Memory
32K Bytes
Ram Size
1.5K Bytes
Speed
40 MHz
Timers
1-8-bit, 3-16-bit
Voltage, Range
2-5.5 V
Lead Free Status / Rohs Status
RoHS Compliant part
Electrostatic Device
Available stocks
Company
Part Number
Manufacturer
Quantity
Price
Company:
Part Number:
PIC18F452-I/L
Manufacturer:
MICROCHIP
Quantity:
1 001
Company:
Part Number:
PIC18F452-I/L
Manufacturer:
Microchip Technology
Quantity:
10 000
Part Number:
PIC18F452-I/L
Manufacturer:
MICROCHIP/微芯
Quantity:
20 000
- Current page: 73 of 332
- Download datasheet (6Mb)
7.0
7.1
An 8 x 8 hardware multiplier is included in the ALU of
the PIC18FXX2 devices. By making the multiply a
hardware operation, it completes in a single instruction
cycle. This is an unsigned multiply that gives a 16-bit
result. The result is stored into the 16-bit product regis-
ter pair (PRODH:PRODL). The multiplier does not
affect any flags in the ALUSTA register.
TABLE 7-1:
7.2
Example 7-1 shows the sequence to do an 8 x 8
unsigned multiply. Only one instruction is required
when one argument of the multiply is already loaded in
the WREG register.
Example 7-2 shows the sequence to do an 8 x 8 signed
multiply. To account for the sign bits of the arguments,
each argument’s Most Significant bit (MSb) is tested
and the appropriate subtractions are done.
EXAMPLE 7-1:
© 2006 Microchip Technology Inc.
MOVF
MULWF
16 x 16 unsigned
8 x 8 unsigned
16 x 16 signed
8 x 8 signed
Routine
8 X 8 HARDWARE MULTIPLIER
Introduction
Operation
ARG1, W
ARG2
PERFORMANCE COMPARISON
8 x 8 UNSIGNED
MULTIPLY ROUTINE
Without hardware multiply
Without hardware multiply
Without hardware multiply
Without hardware multiply
;
; ARG1 * ARG2 ->
;
Hardware multiply
Hardware multiply
Hardware multiply
Hardware multiply
Multiply Method
PRODH:PRODL
Program
Memory
(Words)
13
33
21
24
52
36
1
6
Making the 8 x 8 multiplier execute in a single cycle
gives the following advantages:
• Higher computational throughput
• Reduces code size requirements for multiply
The performance increase allows the device to be used
in applications previously reserved for Digital Signal
Processors.
Table 7-1 shows a performance comparison between
enhanced devices using the single cycle hardware mul-
tiply, and performing the same function without the
hardware multiply.
EXAMPLE 7-2:
Example 7-3 shows the sequence to do a 16 x 16
unsigned multiply. Equation 7-1 shows the algorithm
that is used. The 32-bit result is stored in four registers,
RES3:RES0.
EQUATION 7-1:
RES3:RES0
MOVF
MULWF
BTFSC
SUBWF
MOVF
BTFSC
SUBWF
algorithms
Cycles
(Max)
242
254
91
36
69
24
1
6
ARG1,
ARG2
ARG2,
PRODH, F
ARG2,
ARG1,
PRODH, F
=
=
@ 40 MHz
24.2 s
25.4 s
100 ns
600 ns
6.9 s
9.1 s
2.4 s
3.6 s
ARG1H:ARG1L ARG2H:ARG2L
(ARG1H ARG2H 2
(ARG1H ARG2L 2
(ARG1L ARG2H 2
(ARG1L ARG2L)
SB
SB
W
W
8 x 8 SIGNED MULTIPLY
ROUTINE
16 x 16 UNSIGNED
MULTIPLICATION
ALGORITHM
PIC18FXX2
; ARG1 * ARG2 ->
; PRODH:PRODL
; Test Sign Bit
; PRODH = PRODH
;
; Test Sign Bit
; PRODH = PRODH
;
@ 10 MHz
102.6 s
27.6 s
36.4 s
96.8 s
14.4 s
400 ns
Time
9.6 s
2.4 s
DS39564C-page 71
- ARG1
8
8
16
- ARG2
) +
) +
) +
@ 4 MHz
242 s
254 s
69 s
91 s
24 s
36 s
1 s
6 s
Related parts for PIC18F452-I/L
Image
Part Number
Description
Manufacturer
Datasheet
Request
R
Part Number:
Description:
IC, 8BIT MCU, PIC18F, 40MHZ, LCC-44
Manufacturer:
Microchip Technology
Datasheet:
Part Number:
Description:
IC, 8BIT MCU, PIC18LF, 40MHZ, PLCC-64
Manufacturer:
Microchip Technology
Datasheet:
Part Number:
Description:
IC, 8BIT MCU, PIC18F, 64MHZ, TQFP-80
Manufacturer:
Microchip Technology
Datasheet:
Part Number:
Description:
MCU, MPU & DSP Development Tools CAN/LIN PICtail Plus Daughter Board
Manufacturer:
Microchip Technology
Datasheet:
Part Number:
Description:
IC, 8BIT MCU, PIC18F, 64MHZ, DIP-40
Manufacturer:
Microchip Technology
Datasheet:
Part Number:
Description:
IC, 8BIT MCU, PIC18LF, 40MHZ, PLCC-64
Manufacturer:
Microchip Technology
Datasheet:
Part Number:
Description:
IC, 8BIT MCU, PIC18F, 64MHZ, TQFP-64
Manufacturer:
Microchip Technology
Part Number:
Description:
IC, 8BIT MCU, PIC18F, 64MHZ, TQFP-80
Manufacturer:
Microchip Technology
Part Number:
Description:
8KB, Flash, 768bytes-RAM, 36I/O, 8-bit Family,nanowatt XLP 40 UQFN 5x5x0.5mm TUB
Manufacturer:
Microchip Technology
Datasheet:
Part Number:
Description:
8KB, Flash, 768bytes-RAM, 36I/O, 8-bit Family,nanowatt XLP 40 UQFN 5x5x0.5mm TUB
Manufacturer:
Microchip Technology
Part Number:
Description:
16KB, Flash, 768bytes-RAM, 36I/O, 8-bit Family,nanowatt XLP 40 UQFN 5x5x0.5mm TU
Manufacturer:
Microchip Technology
Datasheet:
Part Number:
Description:
16KB, Flash, 768bytes-RAM, 36I/O, 8-bit Family,nanowatt XLP 40 UQFN 5x5x0.5mm TU
Manufacturer:
Microchip Technology
Part Number:
Description:
32KB, Flash, 1536bytes-RAM, 36I/O, 8-bit Family,nanowatt XLP 40 UQFN 5x5x0.5mm T
Manufacturer:
Microchip Technology
Datasheet:
Part Number:
Description:
32KB, Flash, 1536bytes-RAM, 36I/O, 8-bit Family,nanowatt XLP 40 UQFN 5x5x0.5mm T
Manufacturer:
Microchip Technology
Part Number:
Description:
64KB, Flash, 3968bytes-RAM, 36I/O, 8-bit Family,nanowatt XLP 40 UQFN 5x5x0.5mm T
Manufacturer:
Microchip Technology
Datasheet: