SN8P1602AX datasheet(19/94 Pages) SONIX

19 / 94 page

SN8P1600

8-bit micro-controller

SONiX TECHNOLOGY CO., LTD

Page 19

Revision 1.94

CHECKSUM CALCULATION

The ROM addresses 0004H~0007H and last address are reserved area. User should avoid these addresses

(0004H~0007H and last address) when calculate the Checksum value.

Example:

The demo program shows how to avoid 0004H~0007H when calculated Checksum from 00H to the end of

user’s code

MOV

A,#END_USER_CODE$L

B0MOV

END_ADDR1,A

;save low end address to end_addr1

MOV

A,#END_USER_CODE$

B0MOV

END_ADDR2,A

;save middle end address to end_addr2

CLR

;set Y to ooH

CLR

;set Z to 00H

@@:

CALL

YZ_CHECK

;call function of check yz value

MOVC

;

B0BSET

;clear C glag

ADD

DATA1,A

;add A to Data1

MOV

A,R

ADC

DATA2,A

;add R to Data2

JMP

END_CHECK

;check if the YZ address = the end of code

AAA:

INCMS

;Z=Z+1

JMP

;if Z!= 00H calculate to next address

JMP

Y_ADD_1

;if Z=00H increase Y

END_CHECK:

MOV

A,END_ADDR1

CMPRS

A,Z

;check if Z = low end address

JMP

AAA

;if Not jump to checksum calculate

MOV

A,END_ADDR2

CMPRS

A,Y

;if Yes, check if Y = middle end address

JMP

AAA

;if Not jump to checksum calculate

JMP

CHECKSUM_END

;if Yes checksum calculated is done.

YZ_CHECK:

;check if YZ=0004H

MOV

A,#04H

CMPRS

A,Z

;check if Z=04H

RET

;if Not return to checksum calculate

MOV

A,#00H

CMPRS

A,Y

;if Yes, check if Y=00H

RET

;if Not return to checksum calculate

INCMS

;if Yes, increase 4 to Z

INCMS

RET

;set YZ=0008H then return

Y_ADD_1:

INCMS

;increase Y

NOP

JMP

;jump to checksum calculate

CHECKSUM_END:

……….

END_USER_CODE:

;Label of program end

SN8P1602AX Datenblatt(PDF) 19 Page - SONiX Technology Company

SN8P1602AX Datenblatt(HTML) 19 Page - SONiX Technology Company

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94

Datenblatt Download

Link URL