RCA CDP18S711 ユーザーズマニュアル

34

Memory

Register

Memory

Register

Address

Byte

Address

Byte,

0XB0

0XC0

0XB1

0XC1

0XB2

0XC2

0XB3

R3.0

0XC3

R3.1

0XB4

R4.0

0XC4

R4.1

0XB5

R5.0

0XC5

R5.1

0XB6

R6.0

0XC6

R6.1

0XB7

R7.0

0XC7

R7.1

0XB8

R&0

0XC8

R8.1

0XB9

R9.0

0XC9

R9.1

0XBA

RA.0

0XCA

RA.1

0XBB

RB.0

0XCB

RB.1

0XBC

RC.0

0XCC

RC.1

0XBD

RD.0

0XCD

RD.1

0XBE

RE.0

0XCE

RE.1

0XBF

RF.0

0XCF

RF.1

0X = 07 for 2048-byte RAM

0X = 0B for 3072-byte RAM

0X = 0F for 4096-byte RAM

R5 = CHIP-8 language program counter

RA = CHIP-8 language I pointer

1.

RUN up with key C pressed selects operating

system at 8000.

2. Enter four-digit address followed by mode digit:

5.

A

MR (Memory Read)

0

MW (Memory Write)

B

TR (Tape Read)

F 

TW (Tape Write)

3.

CDP1802 microprocessor registers are stored as

shown in table above. They may be examined after

a program is run by using operating system mode A.

4.

Mode 0 can be used to insert temporary stops in a
program for debugging purposes. Insert a

"branch-to-itself" instruction at the desired stopping

point.

The operating system uses the top 84 bytes of RAM

(0XAC-0XFF). Avoid using these byte locations in

your programs.

6.

The operating system searches for and uses the top

(highest) 256-byte page of on-card RAM. When
RUN is flipped up to execute a program, beginning

at 0000, the following initial conditions exist:

P=0, Q=0, R0=0000, and R1 =0XFF where 0X highest

page of on-card RAM.