8
μ
PD17068
CONTENTS
1.
PIN FUNCTIONS .........................................................................................................................
1.1
LIST OF PIN FUNCTIONS ..............................................................................................................
1.2
EQUIVALENT CIRCUIT OF EACH PIN ..........................................................................................
1.3
HANDLING UNUSED PINS............................................................................................................
1.4
NOTES ON USE OF THE CE AND INT
NC
PINS............................................................................
17
17
21
26
28
2.
PROGRAM MEMORY (ROM) ....................................................................................................
2.1
OUTLINE OF PROGRAM MEMORY..............................................................................................
2.2
PROGRAM MEMORY CONFIGURATION .....................................................................................
2.3
PROGRAM COUNTER ....................................................................................................................
2.3.1
Program Counter Configuration ..................................................................................
2.3.2
Segment Register (SGR) ...............................................................................................
2.4
PROGRAM FLOW ...........................................................................................................................
2.4.1
Branch Instructions........................................................................................................
2.4.2
Subroutines.....................................................................................................................
2.4.3
Table Reference ..............................................................................................................
2.4.4
System Call .....................................................................................................................
2.5
NOTES ON USE OF PROGRAM MEMORY..................................................................................
2.5.1
Program Counter and Program Memory Size ...........................................................
2.5.2
Last Address of Each Segment ....................................................................................
29
29
30
31
31
31
31
31
32
32
32
33
33
33
3.
ADDRESS STACK (ASK)............................................................................................................
3.1
OUTLINE OF ADDRESS STACK....................................................................................................
3.2
ADDRESS STACK REGISTERS (ASR) ..........................................................................................
3.3
STACK POINTER (SP) ....................................................................................................................
3.3.1
Configuration and Function of Stack Pointer ............................................................
3.4
ADDRESS STACK OPERATION.....................................................................................................
3.4.1
Subroutine Call Instruction (“CALL addr” or “CALL @AR”) and
Return Instruction (“RET” or “RETSK”) .....................................................................
3.4.2
Table Reference Instruction (“MOVT DBF, @AR”)....................................................
3.4.3
Interrupt Reception and Return Instruction (“RETI”) ...............................................
3.4.4
Address Stack Manipulation Instructions (“PUSH AR”, “POP AR”) ......................
3.4.5
System Call Instruction (“SYSCAL entry”) and Return Instruction
(“RET” or “RETSK”).......................................................................................................
3.5
NOTES ON USE OF ADDRESS STACK........................................................................................
3.5.1
Nesting Level ..................................................................................................................
34
34
34
36
36
37
37
37
37
37
37
37
37
4.
DATA MEMORY (RAM) .............................................................................................................
4.1
OUTLINE OF DATA MEMORY ......................................................................................................
4.2
CONFIGURATION AND FUNCTIONS OF DATA MEMORY .......................................................
4.2.1
System Register (SYSREG)...........................................................................................
4.2.2
Data Buffer (DBF) ...........................................................................................................
4.2.3
VRAM (Video RAM) for the IDC ...................................................................................
4.2.4
Port Register ...................................................................................................................
4.2.5
General-Purpose Data memory....................................................................................
4.2.6
Unmounted Data Memory ............................................................................................
38
38
39
39
39
39
39
39
39