Figure 7.6.2A Extended Intelligent I/O Service Descriptor Configuration - Fujitsu F2MC-16LX MB90580 Series Hardware Manual

7.6 Extended intelligent I/O service (EI2OS)
(2)Extended intelligent I/O service descriptor (ISD)
The extended intelligent I/O service descriptor exists between 000100
consists of the following items:
Data transfer control data
Status data
Buffer address pointer
Figure 7.6.2a shows the configuration of the extended intelligent I/O service descriptor.
000100
H
ISD start address
Figure 7.6.2a
Data counter (DCT)
This is a 16-bit register that works as a counter corresponding to the number of data items transferred.
This counter is decremented by one before data transfer. EI
0.
Upper byte of data counter
Initial value
Lower byte of data counter
Initial value
94 Chapter 7: Interrupt
High-order 8 bits of data counter (DCTH)
Low-order 8 bits of data counter (DCTL)
High-order 8 bits of I/O address pointer (IOAH)
Low-order 8 bits of I/O address pointer (IOAL)
2
I OS status (ISCS)
High-order 8 bits of buffer address pointer (BAPH)
+ 8 × ICS
Medium-order 8 bits of buffer address pointer (BAPM)
Low-order 8 bits of buffer address pointer (BAPL)
Extended intelligent I/O service descriptor configuration
15 14
B15 B14
(X) (X)
7 6
B07 B06
(X) (X)
2
OS is terminated when this counter reaches
13 12 11
B13 B12 B11 B10
(X) (X) (X)
5 4 3
B05 B04 B03
(X) (X)
(X)
and 00017F in internal RAM, and
H H
H
L
10 9 8
B09 B08
(X) (X) (X)
2 1 0
B02 B01 B00
(X) (X) (X)
MB90580 Series
Bit number
DCTH
Bit number
DCTL