beautypg.com

FUJITSU MB91460 SERIES FR60 User Manual

Page 26

background image

10

Chapter 1 Introduction

4.How to Use This Document

Meaning of Bit Attribute Symbols

R

: Readable

W

: Writable

RM

: Reading operation during read/modify/write operation.

“/” (Slash) R/W: Readable and writable. (The read value is the value written.)

“,” (comma) R,W: Values are different between read and write. (The read value is different from
the value written.)

R0

: The read value is “0”.

R1

: The read value is “1”.

W0

: Always write “0”.

W1

: Always write “1”.

(RM0)

: read/modify/write operation reads “0”.

(RM1)

: read/modify/write operation reads “1”.

RX

: The read value is indeterminate. (Reserved bit or undefined bit)

WX

: Writing does not affect the operation. (Undefined bit)

• Example of how R/W is used

• R/W

: Readable and writable. (The read value is the value written.)

• R,W

: Readable and writable. (The read value and written value are different.)

• R,RM/W

: Readable and writable. (The read value and written value are different. Read/modify/write

command reads the value written.) Example: port data register

• R(RM1),W

: Readable and writable. (The read value and written value are different. Read/modify/write

command reads 1.) Example: interrupt request flag

• R/WX

: Read-only (Read-only. Writing does not affect the operation.)

• R1,W

: Write-only (Write-only. The read value is 1.)

• R0,W

: Write-only (Write-only. The read value is 0.)

• RX,W

: Write-only (Write-only. The read value is indeterminate.)

• R/W0

: Reserved bit (The written value is 0. The read value is the value written.)

• R0/W0

: Reserved bit (The written value is 0. The read value is 0.)

• R1,W0

: Reserved bit (The written value is 0. The read value is 1.)

• RX,W0

: Reserved bit (The written value is 0. The read value is indeterminate.)

• R/W1

: Reserved bit (The written value is 1. The read value is the value written.)

• R1/W1

: Reserved bit (The written value is 1. The read value is 1.)

• R0,W1

: Reserved bit (The written value is 1. The read value is 0.)

• RX,W1

: Reserved bit (The written value is 1. The read value is indeterminate.)

• RX/WX

: Undefined bit (The read value is indeterminate. Writing does not affect the operation.)

• R0/WX

: Undefined bit (The read value is 0. Writing does not affect the operation.)