Fujitsu MB90335 Series Hardware Manual page 98

MB90335 Series
■ Extended Intelligent I/O Service (EI
The extended intelligent I/O service status register (ISCS) updates or fixes the buffer address and I/O
register address pointers by the 8-bit length register. It also indicates the transfer data format (byte or word)
and the direction of transfer. Figure 3.6-5 shows the configuration of the ISCS.
bit7 bit6 bit5
Reserved Reserved Reserved
R/W R/W R/W
R/W : Readable/Writable
X : Undefined
*1 : Buffer address pointer is changed only lower 16-bit and enabled only increment.
*2 : Address pointer is enabled only increment.
CM44-10137-6E
2
Figure 3.6-5 Configuration of EI
bit4 bit3 bit2 bit1
BW BF DIR
IF
R/W R/W R/W R/W
SE
0
It is completed by request from peripheral function.
1
It is not completed by request from peripheral function.
DIR
0
I/O register address pointer
1
Buffer address pointer
BF
0
Buffer address pointer is updated after transfer data. *
1
Buffer address pointer is not updated after transfer data.
BW
0 Byte
1 Word
IF
0
Buffer address pointer is updated after transfer data. *
1
I/O register pointer is not updated after transfer data.
Reserved
Always set this bit to "0".
FUJITSU MICROELECTRONICS LIMITED
3.6 Interrupts by Extended Intelligent I/O Service (EI
OS) Status Register (ISCS)
2
OS Status Register (ISCS)
bit0 Initial value
SE
XXXXXXXX
B
R/W
2
EI OS end control bit
Data transfer direction specification bit
I/O register address pointer
BAP update/fix selection bit
Transfer data length specification bit
IOA update/fix selection bit
Reserved bit.
CHAPTER 3 INTERRUPT
Buffer address pointer
1
2
2
OS)
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