SMBP2501BPB datasheet(18/107 Pages) SONIX

18 / 107 page

SN8P2501B

8-Bit Micro-Controller

SONiX TECHNOLOGY CO., LTD

Page 18

Version 2.1

2.1.1.4

JUMP TABLE DESCRIPTION

The jump table operation is one of multi-address jumping function. Add low-byte program counter (PCL) and ACC

value to get one new PCL. If PCL is overflow after PCL+ACC, PCH adds one automatically. The new program counter

(PC) points to a series jump instructions as a listing table. It is easy to make a multi-jump program depends on the

value of the accumulator (A).



Note:

PCH only support PC up counting result and doesn’t support PC down counting. When PCL is

carry after PCL+ACC, PCH adds one automatically. If PCL borrow after PCL

–ACC, PCH keeps value and

not change.



Example: Jump table.

ORG

0X0100

; The jump table is from the head of the ROM boundary

B0ADD

PCL, A

; PCL = PCL + ACC, PCH + 1 when PCL overflow occurs.

JMP

A0POINT

; ACC = 0, jump to A0POINT

JMP

A1POINT

; ACC = 1, jump to A1POINT

JMP

A2POINT

; ACC = 2, jump to A2POINT

JMP

A3POINT

; ACC = 3, jump to A3POINT

SONIX provides a macro for safe jump table function. This macro will check the ROM boundary and move the jump

table to the right position automatically. The side effect of this macro maybe wastes some ROM size.



Example: I

f “jump table” crosses over ROM boundary will cause errors.

@JMP_A

MACRO

VAL

(($+1) !& 0XFF00) !!= (($+(VAL)) !& 0XFF00)

JMP

($ | 0XFF)

ORG

($ | 0XFF)

ENDIF

ADD

PCL, A

ENDM



Note: “VAL” is the number of the jump table listing number.

SMBP2501BPB Datasheet(PDF) 18 Page - SONiX Technology Company

SMBP2501BPB Datasheet(HTML) 18 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 95 96 97 98 99 100 ...More

Datasheet Download

Link URL