19.5 16-bit Load and Store 20-bit Address

Instruction

clk

A I S Z V C

Operation

 

LDP (HL),HL

12

- - - -

(HL) = L; (HL+1) = H.

 

 

 

(Adr[19:16]

= A[3:0])

LDP (IX),HL

12

- - - -

(IX) = L; (IX+1) = H.

 

 

 

(Adr[19:16]

= A[3:0])

LDP (IY),HL

12

- - - -

(IY) = L; (IY+1) = H.

 

 

 

(Adr[19:16]

= A[3:0])

LDP HL,(HL)

10

- - - -

L = (HL); H

= (HL+1).

 

 

 

(Adr[19:16]

= A[3:0])

LDP HL,(IX)

10

- - - -

L = (IX); H

= (IX+1).

 

 

 

(Adr[19:16]

= A[3:0])

LDP HL,(IY)

10

- - - -

L = (IY); H

= (IY+1).

 

 

 

(Adr[19:16]

= A[3:0])

LDP (mn),HL

15

- - - -

(mn) = L; (mn+1) = H.

 

 

 

(Adr[19:16]

= A[3:0])

LDP (mn),IX

15

- - - -

(mn) = IXL;

(mn+1) = IXH.

 

 

 

(Adr[19:16]

= A[3:0])

LDP (mn),IY

15

- - - -

(mn) = IYL;

(mn+1) = IYH.

 

 

 

(Adr[19:16]

= A[3:0])

LDP HL,(mn)

13

- - - -

L = (mn); H

= (mn+1).

 

 

 

(Adr[19:16]

= A[3:0])

LDP IX,(mn)

13

- - - -

IXL = (mn);

IXH = (mn+1).

 

 

 

(Adr[19:16]

= A[3:0])

LDP IY,(mn)

13

- - - -

IYL = (mn);

IYH = (mn+1).

 

 

 

(Adr[19:16]

= A[3:0])

Note that the LDP instructions wrap around on a 64K page boundary. Since the LDP instruc- tion operates on two-byte values, the second byte will wrap around and be written at the start of the page if you try to read or write across a page boundary. Thus, if you fetch or store at address 0xn,0xFFFF, you will get the bytes located at 0xn,0xFFFF and 0xn,0x0000 instead of 0xn,0xFFFFand 0x(n+1),0x0000 as you might expect. Therefore, do not use LDP at any physical address ending in 0xFFFF.

19.6 Register to Register Moves

Instruction

clk

A

I S Z V C

Operation

LD r,g

2

r

- - - -

r = g, r, g any of B, C, D, E, H, L, A

LD A,EIR

4

fr

* * - -

A = EIR

LD A,IIR

4

fr

* * - -

A = IIR

LD A,XPC

4

r

- - - -

A = MMU

LD EIR,A

4

 

- - - -

EIR = A

LD IIR,A

4

 

- - - -

IIR = A

LD XPC,A

4

 

- - - -

XPC = A

LD HL,IX

4

r

- - - -

HL = IX

LD HL,IY

4

r

- - - -

HL = IY

LD IX,HL

4

 

- - - -

IX = HL

LD IY,HL

4

 

- - - -

IY = HL

LD SP,HL

2

 

- - - -

SP = HL

LD SP,IX

4

 

- - - -

SP = IX

LD SP,IY

4

 

- - - -

SP = IY

LD dd’,BC

4

 

- - - -

dd’ = BC (dd’: 00-BC’, 01-DE’, 10-HL’)

LD dd’,DE

4

 

- - - -

dd’ = DE (dd’: 00-BC’, 01-DE’, 10-HL’)

User’s Manual

251

Page 260
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Jameco Electronics 3000, 2000 manual 19.5 16-bit Load and Store 20-bit Address, Register to Register Moves