PIC18F1230-I/SS Microchip Technology, PIC18F1230-I/SS Datasheet - Page 86

• Manufacturer Part Number: PIC18F1230-I/SS
• Description: Microcontroller
• Manufacturer: Microchip Technology
• Series: PIC® 18Fr

Specifications of PIC18F1230-I/SS

• Core Processor: PIC
• Core Size: 8-Bit
• Speed: 40MHz
• Connectivity: UART/USART
• Peripherals: Brown-out Detect/Reset, LVD, POR, PWM, WDT
• Number Of I /o: 16
• Program Memory Size: 4KB (2K x 16)
• Program Memory Type: FLASH
• Eeprom Size: 128 x 8
• Ram Size: 256 x 8
• Voltage - Supply (vcc/vdd): 4.2 V ~ 5.5 V
• Data Converters: A/D 4x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 20-SSOP
• Package: 20SSOP
• Device Core: PIC
• Family Name: PIC18
• Maximum Speed: 40 MHz
• Operating Supply Voltage: 5 V
• Data Bus Width: 8 Bit
• Number Of Programmable I/os: 16
• Interface Type: USART
• On-chip Adc: 4-chx10-bit
• Number Of Timers: 2
• Processor Series: PIC18F
• Core: PIC
• Data Ram Size: 256 B
• Maximum Clock Frequency: 40 MHz
• Maximum Operating Temperature: + 85 C
• Mounting Style: SMD/SMT
• 3rd Party Development Tools: 52715-96, 52716-328, 52717-734, 52712-325, EWPIC18
• Development Tools By Supplier: PG164130, DV164035, DV244005, DV164005, PG164120, DV164136
• Minimum Operating Temperature: - 40 C
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• For Use With: AC164307 - MODULE SKT FOR PM3 28SSOP
• Lead Free Status / Rohs Status: Details

PIC18F1230/1330
Example 9-3 shows the sequence to do a 16 x 16
unsigned multiplication. Equation 9-1 shows the
algorithm that is used. The 32-bit result is stored in four
registers (RES3:RES0).
EQUATION 9-1:
EXAMPLE 9-3:
Example 9-4 shows the sequence to do a 16 x 16
signed multiply. Equation 9-2 shows the algorithm
used. The 32-bit result is stored in four registers
(RES3:RES0). To account for the sign bits of the
arguments, the MSb for each argument pair is tested
and the appropriate subtractions are done.
DS39758D-page 86
;
;
;
RES3:RES0= ARG1H:ARG1L  ARG2H:ARG2L
MOVF
MULWF
MOVFF
MOVFF
MOVF
MULWF
MOVFF
MOVFF
MOVF
MULWF
MOVF
ADDWF
MOVF
ADDWFC RES2, F
CLRF
ADDWFC RES3, F
MOVF
MULWF
MOVF
ADDWF
MOVF
ADDWFC RES2, F
CLRF
ADDWFC RES3, F
= (ARG1H  ARG2H  2
(ARG1H  ARG2L  2
(ARG1L  ARG2H  2
(ARG1L  ARG2L)
ARG1L, W
ARG2L
PRODH, RES1 ;
PRODL, RES0 ;
ARG1H, W
ARG2H
PRODH, RES3 ;
PRODL, RES2 ;
ARG1L, W
ARG2H
PRODL, W
RES1, F
PRODH, W
WREG
ARG1H, W
ARG2L
PRODL, W
RES1, F
PRODH, W
WREG
16 x 16 UNSIGNED
MULTIPLICATION
ALGORITHM
16 x 16 UNSIGNED
MULTIPLY ROUTINE
; ARG1L * ARG2L->
; PRODH:PRODL
; ARG1H * ARG2H->
; PRODH:PRODL
; ARG1L * ARG2H->
; PRODH:PRODL
;
; Add cross
; products
;
;
;
;
; ARG1H * ARG2L->
; PRODH:PRODL
;
; Add cross
; products
;
;
;
8
8
16
) +
) +
) +
EQUATION 9-2:
EXAMPLE 9-4:
RES3:RES0= ARG1H:ARG1L  ARG2H:ARG2L
;
;
;
;
;
SIGN_ARG1
;
CONT_CODE
:
MOVF
MULWF
MOVFF
MOVFF
MOVF
MULWF
MOVFF
MOVFF
MOVF
MULWF
MOVF
ADDWF
MOVF
ADDWFC RES2, F
CLRF
ADDWFC RES3, F
MOVF
MULWF
MOVF
ADDWF
MOVF
ADDWFC RES2, F
CLRF
ADDWFC RES3, F
BTFSS
BRA
MOVF
SUBWF
MOVF
SUBWFB RES3
BTFSS
BRA
MOVF
SUBWF
MOVF
SUBWFB RES3
= (ARG1H  ARG2H  2
(ARG1H  ARG2L  2
(ARG1L  ARG2H  2
(ARG1L  ARG2L) +
(-1  ARG2H<7>  ARG1H:ARG1L  2
(-1  ARG1H<7>  ARG2H:ARG2L  2
ARG1L, W
ARG2L
PRODH, RES1 ;
PRODL, RES0 ;
ARG1H, W
ARG2H
PRODH, RES3 ;
PRODL, RES2 ;
ARG1L, W
ARG2H
PRODL, W
RES1, F
PRODH, W
WREG
ARG1H, W
ARG2L
PRODL, W
RES1, F
PRODH, W
WREG
ARG2H, 7
SIGN_ARG1
ARG1L, W
RES2
ARG1H, W
ARG1H, 7
CONT_CODE
ARG2L, W
RES2
ARG2H, W
16 x 16 SIGNED
MULTIPLICATION
ALGORITHM
16 x 16 SIGNED
MULTIPLY ROUTINE
 2009 Microchip Technology Inc.
; ARG1L * ARG2L ->
; PRODH:PRODL
; ARG1H * ARG2H ->
; PRODH:PRODL
; ARG1L * ARG2H ->
; PRODH:PRODL
;
; Add cross
; products
;
;
;
;
; ARG1H * ARG2L ->
; PRODH:PRODL
;
; Add cross
; products
;
;
;
; ARG2H:ARG2L neg?
; no, check ARG1
;
;
;
; ARG1H:ARG1L neg?
; no, done
;
;
;
8
8
16
) +
) +
) +
16
16
) +
)