
S3C8248/C8245/P8245/C8247/C8249/P8249
INSTRUCTION SET
6-41
ENTER
—
Enter
ENTER
Operation:
SP
←
SP – 2
@SP
←
IP
IP
←
PC
PC
←
@IP
IP
←
IP + 2
This instruction is useful when implementing threaded-code languages. The contents of the
instruction pointer are pushed to the stack. The program counter (PC) value is then written to the
instruction pointer. The program memory word that is pointed to by the instruction pointer is
loaded into the PC, and the instruction pointer is incremented by two.
Flags:
No flags are affected.
Format:
Bytes
Cycles
Opcode
(Hex)
opc
1
14
1F
Example:
The diagram below shows one example of how to use an ENTER statement.
0050
IP
0022
SP
22
Data
Address
Data
0040
PC
40
41
42
43
Enter
Address H
Address L
Address H
Address
Data
1F
01
10
Memory
0043
IP
0020
SP
20
21
22
IPH
IPL
Data
Address
Data
0110
PC
40
41
42
43
Enter
Address H
Address L
Address H
Address
Data
1F
01
10
Memory
00
50
Stack
Stack
110
Routine
Before
After
Summary of Contents for C8245
Page 31: ...ADDRESS SPACES S3C8248 C8245 P8245 C8247 C8249 P8249 2 20 NOTES ...
Page 107: ...INTERRUPT STRUCTURE S3C8248 C8245 P8245 C8247 C8249 P8249 5 18 NOTES ...
Page 195: ...INSTRUCTION SET S3C8248 C8245 P8245 C8247 C8249 P8249 6 88 NOTES ...
Page 221: ...I O PORTS S3C8248 C8245 P8245 C8247 C8249 P8249 9 16 NOTES ...
Page 245: ...16 BIT TIMER 0 1 S3C8248 C8245 P8245 C8247 C8249 P8249 12 10 NOTES ...
Page 249: ...WATCH TIMER S3C8248 C8245 P8245 C8247 C8249 P8249 13 4 NOTES ...
Page 267: ...A D CONVERTER S3C8248 C8245 P8245 C8247 C8249 P8249 15 6 NOTES ...
Page 299: ...S3P8245 P8249 OTP S3C8248 C8245 P8245 C8247 C8249 P8249 21 8 NOTES ...
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