Operation Of Extended Intelligent I/O Service (Ei 2 Os) - Fujitsu MB90335 Series Hardware Manual

MB90335 Series
3.6.3 Operation of Extended Intelligent I/O Service (EI
If the peripheral function has generated an interrupt request and activation of EI
been set in the associated interrupt control register (ICR), the CPU will execute data
2
transfer using EI OS. Once data transfer has been executed the specified number of
times, the hardware interrupt handling is executed automatically.
■ Operation of Extended Intelligent I/O Service (EI
Figure 3.6-7 shows the EI
Figure 3.6-7 Flow Chart of Operation of Extended Intelligent I/O Service (EI
ISD
ISCS : EI
IF
BW : Transfer data length specification bit of
BF
DIR : Transfer data direction specification bit of
SE
CM44-10137-6E
2
OS operation flow chart by the microcode of the internal CPU.
Generation of interrupt
request from peripheral
function
NO
ISE=1
YES
ISD/ISCS read
End request
YES
from peripheral
function
NO
YES
DIR=1
NO
Data indicated by IOA
(Data transfer)
Memo indicated by BAP
YES
IF=0
NO
YES
BF=0
NO
(-1)
DCT decrement
YES
DCT=00
NO
Set "00" to S1,S0
Clearing peripheral
function interrupt request
CPU operation return
2
: EI OS descriptor
2
OS status register (ISCS)
: IOA update/fix selection bit of
2
EI OS status register (ISCS)
2
EI OS status register (ISCS)
: BAP update/fix selection bit of
2
EI OS status register (ISCS)
2
EI OS status register (ISCS)
2
: EI OS end control bit of
2
EI OS status register (ISCS)
FUJITSU MICROELECTRONICS LIMITED
3.6 Interrupts by Extended Intelligent I/O Service (EI
2
OS)
Interrupt sequence
SE=1
NO
Data indicated by BAP
(Data transfer)
Memo indicated by IOA
Update value
IOA update
by BW
Update value
BAP update
by BW
2
EI OS end processing
Set "01" to S1,S0 Set "11" to S1,S0
Clearing ISE to "0"
Interrupt sequence
DCT : Data counter
: I/O register address pointer
IOA
BAP : Buffer address pointer
2
: EI OS enable bit of Interrupt control register (ICR)
ISE
2
S1,S0 : EI OS status bit of Interrupt control register (ICR)
CHAPTER 3 INTERRUPT
2
OS)
2
2
OS)
YES
2
OS)
OS has
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