KS57C2308/P2308/C2316/P2316
ADDRESS SPACES
2-11
+
+
PROGRAMMING TIP
—
Selecting the Working Register Area
The following examples show the correct programming method for selecting working register area:
1.
When ERB = "0":
VENT2
1,0,INT0
; EMB
←
1, ERB
←
0, Jump to INT0 address
INT0
PUSH
SB
; PUSH current SMB, SRB
SRB
2
; Instruction does not execute because ERB = "0"
PUSH
HL
; PUSH HL register contents to stack
PUSH
WX
; PUSH WX register contents to stack
PUSH
YZ
; PUSH YZ register contents to stack
PUSH
EA
; PUSH EA register contents to stack
SMB
0
LD
EA,#00H
LD
80H,EA
LD
HL,#40H
INCS
HL
LD
WX,EA
LD
YZ,EA
POP
EA
; POP EA register contents from stack
POP
YZ
; POP YZ register contents from stack
POP
WX
; POP WX register contents from stack
POP
HL
; POP HL register contents from stack
POP
SB
; POP current SMB, SRB
IRET
The POP instructions execute alternately with the PUSH instructions. If an SMB n instruction is used in an
interrupt service routine, a PUSH and POP SB instruction must be used to store and restore the current SMB and
SRB values, as shown in Example 2 below.
2.
When ERB = "1":
VENT2
1,1,INT0
; EMB
←
1, ERB
←
1, Jump to INT0 address
INT0
PUSH
SB
; Store current SMB, SRB
SRB
2
; Select register bank 2 because of ERB = "1"
SMB
0
LD
EA,#00H
LD
80H,EA
LD
HL,#40H
INCS
HL
LD
WX,EA
LD
YZ,EA
POP
SB
; Restore SMB, SRB
IRET
Summary of Contents for KS57C2308
Page 30: ...ADDRESS SPACES KS57C2308 P2308 C2316 P2316 2 22 NOTES ...
Page 168: ...SAM47 INSTRUCTION SET KS57C2308 P2308 C2316 P2316 5 94 NOTES ...
Page 170: ......
Page 206: ...POWER DOWN KS57C2308 P2308 C2316 P2316 8 8 NOTES ...
Page 210: ...RESET KS57C2308 P2308 C2316 P2316 9 4 NOTES ...
Page 222: ...I O PORTS KS57C2308 P2308 C2316 P2316 10 12 NOTES ...
Page 272: ...LCD CONTROLLER DRIVER KS57C2308 P2308 C2316 P2316 12 24 NOTES ...
Page 280: ...SERIAL I O INTERFACE KS57C2308 P2308 C2316 P2316 13 8 NOTES ...
Page 294: ...MECHANICAL DATA KS57C2308 P2308 C2316 P2316 15 2 NOTES ...
Page 310: ...KS57P2308 P2316 OTP KS57C2308 P2308 C2316 P2316 16 16 NOTES ...
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