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2-10
Functional Description
Figure 2.5
Programmed I/O Target Transfers
Set Info. Transfer
(0xFC03 Bits [2:0]
Phase
ACK/
Active?
(0xFC05, Bit 0)
No
Yes
Target Receive
Set Info. Transfer
(0xFC03 Bits [2:0]
Phase
Target Send
Set Transfer
Memory
Counter in
Write Data to
(Reg. 0xFC00)
Output Data Reg.
Target Send Only
Set Assert Data
(Reg. 0xFC01, Bit 0)
Bus Bit
Target Send Only
Set Assert
(0xFC03, Bit 3)
REQ/ Bit
Reset Assert
(0xFC03, Bit 3)
REQ/ Bit
Read Data from
(Reg. 0xFC00)
SCSI Data Reg.
ACK/
Inactive?
(0xFC05, Bit 0)
No
Yes
Decrement
In Memory
Transfer Counter
Transfer
Counter
Equal Zero
No
Yes
?
Target Receive Only
A
A
Go to Next Phase
Содержание Symbios SYM53C040
Страница 12: ...xii Preface...
Страница 90: ...4 18 SCSI and DMA Registers...
Страница 98: ...5 8 SFF 8067 Registers...
Страница 110: ...6 12 Two Wire Serial Registers...
Страница 126: ...7 16 Miscellaneous Registers...
Страница 160: ...8 34 System Registers...
Страница 184: ...9 24 Electrical Characteristics...
Страница 194: ...A 10 Register Summary...
Страница 214: ......