Epson 6200A 2.1.1 Program counter block, 2.1.2 Flags

4EPSON S1C6200/6200A CORE CPU MANUAL

2 MEMORY AND OPERATIONS

2.1.1 Program counter block

The program counter is used to point to the next instruction step to be executed by the CPU. See Figure

2.1.1.1.

The program counter has the following registers.

Table 2.1.1.1 Program counter registers

PCB (Program Counter-Bank)

PCP (Program Counter-Page)

PCS (Program Counter-Step)

NBP (New Bank Pointer)

NPP (New Page Pointer)

Register Size

1-bit register

4-bit counter

8-bit counter

1-bit register

4-bit register

Program memory

(8,192 12-bit words max.)

Program counter block

Address decoder

PCB

(1)

NBP

(1)

PCP

(4)

NPP

(4)

PCS

(8)

Fig. 2.1.1.1 Program counter configuration

PCB, PCP and PCS together from a 13-bit counter which can address any location in program memory.

PCP and PCS together from a 12-bit counter which can address any location within a given bank of pro-

gram memory. Each time an instruction other than a jump is executed, this counter increments by one.

Thus, a jump instruction does not need to be executed between the last step of one page and the first step of

the next.

The contents of NBP and NPP are loaded into PCB and PCP each time an instruction is executed. On reset,

NBP and NPP are loaded with the same values as PCB and PCP.

2.1.2 Flags

The following flags are provided.

Table 2.1.2.1 Flags

Interrupt

Decimal mode

Zero

Carry

Flag Size

1: Enabled

0: Disabled

1: Decimal

0: Hexadecimal

1: Set

0: Ignored

1: Set

0: Ignored

Menus

I

D

Z

C

Contents

Main NOTICE SEIKO EPSON CORPORATION 2001, All rights reserved. Configuration of product number Devices S1 C 60N01 F 0A01 Development tools S5U1 C 60R08 D1 1 00 Page S1C6200/6200A Core CPU Manual CONTENTS 1D 2M 3I B. INSTRUCTION INDEX ______________________________________ 87 Page 1D 1.1 System Features 1.2 Instruction Set Features 1.3 Differences between S1C6200 and S1C6200A 1 DESCRIPTION S1C6200 CORE CPU 8-bit address bus13-bit address bus Fig. 1.1 Block diagram 4-bit data bus S1C6200/6200A CORE CPU MANUAL EPSON 3 2M Fig. 2.1.1 Program memory configuration (within bank) PCB (between banks) 2.1 Program Memory (ROM) 2.1.1 Program counter block 2.1.2 Flags 2.1.3 Jump instructions 2.1.4 PSET with jump instructions 2.1.5 Call instructions 2.1.6 PSET instruction 2.1.7 CALZ instruction Fig. 2.1.7.1 The use of the CALZ instruction Bank 0 Page 0 EEE.................... RET 2.1.8 RET and RETS instructions Bank 0 Page 0 Program memory PSET CALL LD LD Bank 0 Page 10 Program memory DDD.................... RET RETS 2.2 Data Memory (within page) (page specification) 4-bit data Memory or I/O Register area Index register IY Stack pointer SP Register pointer RP 2.3 ALU (Arithmetic Logic Unit) and Registers Operation Instruction ADD ADC SUB SBC AND OR XOR CP FAN RRC RLC NOT 2.3.1 D (decimal) flag and decimal operations 2.3.2 A and B registers 2.4 Timing Generator 5-clock/7-clock instructions 12-clock instructions 2.4.1 HALT and SLP (sleep) modes 2.5 Interrupts 2.5.1 Interrupt vectors 2.5.2 I (interrupt) flag 2.5.3 Operation during interrupt generation Fig. 2.5.3.1 Interrupt timing during execution S1C6200/6200A CORE CPU MANUAL EPSON 13 S1C6200 S1C6200A Fig. 2.5.3.2 Interrupt timing in the HALT mode Fig. 2.5.3.3 Interrupt timing in SLEEP mode Fig. 2.5.3.4 Interrupt timing with PSET System clock CPU clock Status Instruction S1C6200/6200A S1C6200 2.5.4 Initial reset On reset, the registers and flags are set as shown in Table 2.5.4.1. Table 2.5.4.1 Reset value 3I 3.1 Instruction Indices a. Index by function b. Index in alphabetical order c. Index by operation code 3.1.1 By function Page Page 3.1.2 In alphabetical order Page Page 3.1.3 By operation code Page Page 3.2 Operands n n 3.3 Flags 1. Carry flag 3.4 Instruction Types (I) (II) (III) (IV) ACPX MX,r ACPY MY,r ADC r,i ADC r,q ADC XH,i ADC XL,i ADC YH,i ADC YL,i ADD r,i ADD r,q AND r,i AND r,q CALL s CALZ s CP r,i CP r,q CP XH,i CP XL,i CP YH,i CP YL,i DEC Mn DEC SP Decrement memory DI EI FAN r,i FAN r,q INC Mn HALT Increment stack pointer by 1INC SP INC X INC Y JPBA JP C,s JP NC,s JP NZ,s JP s JP Z,s LBPX MX,e LD A,Mn LD B,Mn LD Mn,A LD Mn,B LDPX MX,i LDPX r,q LDPY MY,i LDPY r,q LD r,i LD r,q LD r,SPH LD r,SPL LD r,XH LD r,XL LD r,XP LD r,YH LD r,YL LD r,YP LD SPH,r LD SPL,r LD X,e LD XH,r LD XL,r LD XP,r LD Y,e LD YH,r LD YL,r LD YP,r NOP5 NOP7 NOT r OR r,i OR r,q POP F POP r POP XH = XH POP XL = XL POP XP POP YH = YH POP YL POP YP = YP PSET p PUSH F PUSH r = r-register PUSH XH PUSH XL PUSH XP PUSH YH PUSH YL PUSH YP = YP RCF RDF RET RETD e Load immediate data e to memory, and increment X by 2, then return RETS RLC r RRC r r-register C RST F,i Cd r-register CC RZF SBC r,i SBC r,q SCF SCPX MX,r SCPY MY,r SDF SET F,i SLP SUB r,q SZF XOR r,i XOR r,q ABBREVIATIONS APPENDIX A. S1C6200A (ADVANCED S1C6200) CORE CPU A1 Outline of Differences A2 Detailed Description of the Differences A2.1 Initial reset A2.2 Interrupt Operation during interrupt issuance b) At HALT mode c) During "PSET" instruction execution Fig. A2.2.1 Timing chart of S1C6200A interrupt a) During instruction execution Clock Status Instruction System clock CPU clock Status Instruction <Reference 1> Writing on the interrupt mask register during EI <Reference 2> Reading the interrupt factor flag during EI Page L N O P P R S X International Sales Operations AMERICA EUROPE ASIA