Epson S1C63000 2.1.4 Arithmetic operations with numbering system

CHAPTER 2: ARCHITECTURE

2.1.4 Arithmetic operations with numbering system

In the S1C63000, some instructions support a numbering system. These instructions are indicated with the following notations in the instruction list.

ADC operand,n4

SBC operand,n4

INC operand,n4

DEC operand,n4

(See "Instruction List" or "Detailed Explanation of Instructions" for the contents of the operand.)

"n4" is a radix, and can be specified from 1 to 16. The additions/subtractions are done in the numbering system with n4 as the radix. Various counters (such as binary, octal, decimal and hexadecimal) can be realized easily by software.

The Z flag indicates that an operation result is "0" or not in arithmetics with any numbering system. The C flag indicates a carry/borrow according to the radix.

The following shows examples of these operation.

Example 1) Octal addition ADC %B,%A,8 (C flag is "0" before operation)

Setting value		Result		F register
B register	A register	B register	E	I	C	Z
0010B(2)	0111B(7)	0001B(1)	0	–	1	0
0101B(5)	0011B(3)	0000B(0)	0	–	1	1

Example 2) Decimal subtractio SBC %B,%A,10 (C flag is "0" before operation)

Setting value		Result		F register
B register	A register	B register	E	I	C	Z
1001B(9)	0111B(7)	0010B(2)	0	–	0	0
0001B(1)	0010B(2)	1001B(9)	0	–	1	0

Example 3) 3-digit BCD down counter

LDB	%EXT,0	; Counter base address [0010H]
LD	%XL,0x10
LDB	[%X]+,0	; Initial value setting [100]
LDB	[%X]+,0
LDB	[%X]+,1
:
:
CTDOWN:		; Count down subroutine----------
LDB	%EXT,0	; Counter base address [0010H]
LD	%XL,0x10
DEC	[%X]+,10	; Decrements digit 1
SBC	[%X]+,0,10	; Decrements carry from digit 2
SBC	[%X],0,10	; Decrements carry from digit 3
CALR	CTDISP	; Count number display routine
LD	%A,0	; Zero check
ADD	%A,[%X]
ADD	%X,-1
ADD	%A,[%X]
ADD	%X,-1
JRNZ	CTEXIT	; Return if counter is not zero
CALR	CTOVER	; Count over processing routine
CTEXIT:
RET

This routine constructs a 3-digit BCD counter using the decimal operation instructions underlined. Calling the CTDOWN subroutine decrements the counter, and then returns to the main routine. If the counter has to be zero, the CTOVER subroutine is called before returning to the main routine to process the end of counting.

S1C63000 CORE CPU MANUAL

EPSON

7

Contents

Page © SEIKO EPSON CORPORATION 2001 All rights reserved SEIKO EPSON CORPORATION The information of the product number change Configuration of product number Devices Development tools Comparison table between new and previous number Page S1C63000 CORE CPU MANUAL PREFACE CONTENTS CHAPTER 4 INSTRUCTION SET CHAPTER 1 OUTLINE 1.1 Features 1.2 Instruction Set Features 1.3 Block Diagram 1.4 Input-OutputSignals Table 1.4.1(b) Input/output signal list (2) Data bus I00–I12 Instruction bus Inputs an instruction code CHAPTER 2 ARCHITECTURE 2.1 ALU and Registers 2.1.1 ALU 2.1.2 Register configuration •A and B registers 2.1.3 Flags •Z (zero) flag •C (carry) flag •I flag •E (extension mode) flag •Flag operations 2.1.4 Arithmetic operations with numbering system •Notes in numbering operations 2.1.5 EXT register and data extension (1)Operation for EXT register and E flag (flag register) (2)Extension with E flag •16-bitdata transfer/arithmetic for the index registers X and Y •Extending branch addresses 2.2 Program Memory 2.2.1 Configuration of program memory 2.2.2 PC (program counter) 2.2.3 Branch instructions •PC relative jump instructions (JR) •Indirect jump instruction (JP) •Absolute call instruction (CALZ) •PC relative call instructions (CALR) Page •Return instructions (RET, RETS, RETD, RETI) •Software interrupt instruction (INT) 2.2.4 Table look-upinstruction 2.3 Data Memory 2.3.1 Configuration of data memory 2.3.2 Addressing for data memory •Accessing for addresses 0000H to 00FFH •Accessing for addresses FF00H to FFFFH (I/O memory area) •Accessing for addresses 0000H to 003FH •Accessing for addresses FFC0H to FFFFH (I/O memory area) 2.3.3 Stack and stack pointer (1)Stack pointer SP1 (2)Stack pointer SP2 (3) Notes for using the stack pointer 2.3.4 Memory mapped I/O CHAPTER 3 CPU OPERATION 3 CPU O 3.1 Timing Generator and Bus Cycle 3.2 Instruction Fetch and Execution 3.3 Data Bus (Data Memory) Control 3.3.1 Data bus status 3.3.2 High-impedancecontrol 3.3.3 Interrupt vector read 3.3.4 Memory write 3.3.5 Memory read 3.4 Initial Reset 3.4.1 Initial reset sequence 3.4.2 Initial setting of internal registers 3.5 Interrupts 3.5.1 Interrupt vectors 3.5.2 Interrupt sequence •Hardware interrupts Page Page •Software interrupts 3.5.3 Notes for interrupt processing 3.6 Standby Status 3.6.1 HALT status 3.6.2 SLEEP status Page CHAPTER 4 INSTRUCTION SET 4.1 Addressing Mode •Types of addressing modes 4.1.1 Basic addressing modes •Immediate data addressing •Register direct addressing •Register indirect addressing •6-bitabsolute addressing •Signed 8-bitPC relative addressing 4.1.2 Extended addressing mode •16-bitimmediate data addressing •8-bitabsolute addressing •Signed 16-bitPC relative addressing 4.2 Instruction List 4.2.1 Function classification 4.2.2 Symbol meanings Register names Immediate data Memory Flags Operations and others Extended addressing mode (EXT.mode) 4.2.3 Instruction list by function ALU alithmetic operation (1/3) ALU alithmetic operation (2/3) ALU alithmetic operation (3/3) ALU logic operation (1/2) ALU logic operation (2/2) ALU shift and rotate operation 8/16-bitoperation Stack operation Branch control System control 4.2.4 List in alphabetical order Page Page Page Page Page Page 4.2.5 List of extended addressing instructions 8-bitabsolute addressing (2/4) 8-bitabsolute addressing (3/4) 8-bitabsolute addressing (4/4) 4.3 Instruction Formats 4.4 Detailed Explanation of Instructions ADC %r,%r ADC %r,imm4 ADC %r,[%ir] ADC %r,[%ir]+ ADC [%ir],%r ADC [%ir]+,%r ADC [%ir],imm4 ADC [%ir]+,imm4 ADC %B,%A,n4 ADC %B,[%ir],n4 ADC %B,[%ir]+,n4 ADC [%ir],%B,n4 ADC [%ir]+,%B,n4 ADC [%ir],0,n4 ADC [%ir]+,0,n4 ADD %r,%r ADD %r,imm4 ADD %r,[%ir] ADD %r,[%ir]+ ADD [%ir],%r ADD [%ir]+,%r ADD [%ir],imm4 ADD [%ir]+,imm4 ADD %ir,%BA ADD %ir,sign8 AND %r,%r AND %r,imm4 AND %F,imm4 AND %r,[%ir] AND %r,[%ir]+ AND [%ir],%r AND [%ir]+,%r AND [%ir],imm4 AND [%ir]+,imm4 BIT %r,imm4 %r,[%ir]+ [%ir],%r [%ir]+,%r BIT [%ir],imm4 BIT [%ir]+,imm4 CALR [addr6] CALR sign8 CALZ imm8 CLR [addr6],imm2 CMP %r,%r’ CMP %r,imm4 CMP %r,[%ir] CMP %r,[%ir]+ CMP [%ir],%r CMP [%ir]+,%r CMP [%ir],imm4 CMP [%ir]+,imm4 CMP %ir,imm8 DEC [addr6] DEC [ir],n4 DEC [ir]+,n4 DEC %sp EX %A,%B EX %r,[%ir] EX %r,[%ir]+ HALT INC [addr6] INC [ir],n4 INC [ir]+,n4 INC %sp INT imm6 JP %Y JR %A JR %BA JR [addr6] JR sign8 JRC sign8 JRNC sign8 JRNZ sign8 JRZ sign8 LD %r,%r’ LD %r,imm4 LD %r,[%ir] LD %r,[%ir]+ LD [%ir],%r LD [%ir]+,%r LD [%ir],imm4 LD [%ir]+,imm4 LD [%ir],[%ir’] LD [%ir],[%ir’]+ LD [%ir]+,[%ir’] LD [%ir]+,[%ir’]+ LDB %BA,imm8 LDB %BA,[%ir]+ LDB %BA,%EXT LDB %BA,%rr LDB %BA,%sp LDB [%ir]+,%BA LDB [%X]+,imm8 LDB %EXT,imm8 LDB %EXT,%BA LDB %rr,imm8 LDB %rr,%BA LDB %sp,%BA NOP OR %r,%r’ OR %r,imm4 OR %F,imm4 OR %r,[%ir] OR %r,[%ir]+ OR [%ir],%r OR [%ir]+,%r OR [%ir],imm4 OR [%ir]+,imm4 POP %r POP %ir PUSH %r PUSH %ir RET RETD imm8 RETI RETS RL %r RL [%ir] RL [%ir]+ RR %r RR [%ir] RR [%ir]+ SBC %r,%r SBC %r,imm4 SBC %r,[%ir] SBC %r,[%ir]+ SBC [%ir],%r SBC [%ir]+,%r SBC [%ir],imm4 SBC [%ir]+,imm4 SBC %B,%A,n4 SBC %B,[%ir],n4 SBC %B,[%ir]+,n4 SBC [%ir],%B,n4 SBC [%ir]+,%B,n4 SBC [%ir],0,n4 SBC [%ir]+,0,n4 SET [addr6],imm2 SLL %r SLL [%ir] SLL [%ir]+ SLP SRL %r SRL [%ir] SRL [%ir]+ SUB %r,%r’ SUB %r,imm4 SUB %r,[%ir] SUB %r,[%ir]+ SUB [%ir],%r SUB [%ir]+,%r SUB [%ir],imm4 SUB [%ir]+,imm4 TST [addr6],imm2 XOR %r,%r’ XOR %r,imm4 XOR %F,imm4 XOR %r,[%ir] XOR %r,[%ir]+ XOR [%ir],%r XOR [%ir]+,%r XOR [%ir],imm4 XOR [%ir]+,imm4 Index AMERICA EUROPE ASIA In pursuit of “Saving” Technology, Epson electronic devices “Saving” Technology Our lineup of semiconductors, liquid crystal displays and quartz devices assists in creating the products of our customers’ dreams Epson IS energy savings Core CPU Manual