Toshiba TC9349AFG Manual page 47

3. I/O access of a stack register
The stack register is arranged in the I/O map. Therefore reading the state of the stack register and rewriting data are
possible. The contents of an address stack pointer (ASP) or an interruption stack pointer (ISP) can also be accessed. These
data are accessed with an OUT1/IN1 instruction for which [CN = 0H] is specified for the operand, and divided and arranged
by the data selection function.
The address stack register and the interrupt stack register have 16 and four pages respectively. When these ports are
accessed with the I/O instruction, the page is specified before the stack register is accessed. The address stack selection
specifies the page of the address stack register. The interrupt stack selection specifies the page of the interrupt stack register.
Rewriting of address stack registers is set from low-ranking bit, while the 14 address stack register bits are updated by
accessing high-ranking bits. Therefore care is required: it is still necessary to access the high-ranking bits even when only
low-ranking bits are being changed.
φL/K10(0)
Y1 Y2 Y4 Y8
ASP ASP ASP ASP
0 1 2 3
Address stack pointer
nesting level is setting / detectable.
φL/K10(1)
Y1 Y2 Y4 Y8
ASS ASS ASS ASS
0 1 2 3
Address stack select
φL/K10(2)
φL/K10(3)
φL/K10(4)
φL/K10(5)
Page 0
1
Note: The program memory area is 16 kilobytes and 13 bits are used. Therefore it is necessary to set the most
significant bit (ASR13) of the address stack to "0".
Address stack register
Y1 Y2 Y4 Y8
ASR0 ASR1 ASR2 ASR3
ASR4 ASR5 ASR6 ASR7
ASR8 ASR9 ASR10 ASR11
ASR12 ASR13 */0 */0
2
3
15
47
φL/K10(0)
Y1 Y2 Y4 Y8
ISP0 ISP1 */0 */0
Interrupt stack pointer
nesting level is setting / detectable.
φL/K10(7)
Y1 Y2 Y4 Y8
ISS0 ISS1 */0 */0
Interrupt stack select
Interrupt stack register
Y1
φL/K10(8)
ISRG0 ISRG1 ISRG2 ISRG3
φL/K10(9)
ISRG4
φL/K10(A)
ISRS0 ISRS1 SEL4 ISRS2
φL/K10(B)
ISRCA
φL/K10(C)
ISRd0 ISRd1 ISRd2 ISRd3
φL/K10(D)
ISRd4 ISRd5 ISRd6 ISRd7
φL/K10(E)
ISRd8 ISRd9
φL/K10(F)
ISRd1
2
Page 0
1
2
TC9349AFG
Y2 Y4 Y8
*/0 */0 */0
*/0 */0 */0
ISRd1 ISRd1
0 1
ISRd1 ISRd1 ISRd1
3 4 5
3
2006-02-24