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7 compare instructions, Ske reg, #n4, Ske @hl, #n4 – NEC PD754144 User Manual

Page 274: Ske a, @hl, Ske xa, @hl, Ske a, reg, Ske xa, rp

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CHAPTER 11 INSTRUCTION SET

274

User’s Manual U10676EJ3V0UM

11.4.7 Compare instructions

SKE reg, #n4

Function: Skip if reg = n4 n4 = I

3-0

: 0-FH

Skips the next instruction if the contents of register reg (X, A, H, L, D, E, B, or C) are equal to 4-bit immediate data

n4.

SKE @HL, #n4

Function: Skip if (HL) = n4 n4 = I

3-0

: 0-FH

Skips the next instruction if the contents of the data memory addressed by register pair HL are equal to 4-bit

immediate data n4.

SKE A, @HL

Function: Skip if A = (HL)

Skips the next instruction if the contents of the A register are equal to the contents of the data memory addressed

by register pair HL.

SKE XA, @HL

Function: Skip if A = (HL) and X = (HL + 1)

Skips the next instruction if the contents of the A register are equal to the contents of the data memory addressed

by register pair HL and if the contents of the X register are equal to the contents of the next memory address.

However, if the contents of the L register are an odd number, an address whose least significant address is ignored

is specified.

SKE A, reg

Function: Skip if A = reg

Skips the next instruction if the contents of the A register are equal to register reg (X, A, H, L, D, E, B, or C).

SKE XA, rp’

Function: Skip if XA = rp’

Skips the next instruction if the contents of register pair XA are equal to the contents of register pair rp’ (XA, HL,

DE, BC, XA’, HL’, DE’, or BC’).

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