P R E L I M I N A R Y
AMD
24
Am53CF94/Am53CF96
Initiator Select without
ATN
Steps
Internal State
Register (06H)
Bits 2:0 (Hex)
0
4
3
Interrupt Status
Register (05H)
Bits 7:0 (Hex)
20
18
18
Explanation
Arbitration steps completed. Selection time-out occurred, then disconnected
Selection without
ATN
steps fully executed
Sequence halted during command transfer due to premature phase change
(Target)
Arbitration and selection completed; sequence halted because Target failed to
assert command phase
2
18
Initiator Select with
ATN
Steps
Internal State
Register (06H)
Bits 2:0 (Hex)
0
4
3
Interrupt Status
Register (05H)
Bits 7:0 (Hex)
20
18
18
Explanation
Arbitration steps completed. Selection time-out occurred then disconnected
Selection with
ATN
steps fully executed
Sequence halted during command transfer due to premature phase change;
some CDB bytes may not have been sent; check FIFO flags
Message out completed; sent one message byte with
ATN
true, then released
ATN
; sequence halted because Target failed to assert command phase after
message byte was sent
Arbitration and selection completed; sequence halted because Target did not
assert message out phase;
ATN
still driven by ESC
2
18
0
18
Initiator Select with
ATN3
Steps
Internal State
Register (06H)
Bits 2:0 (Hex)
0
4
3
Interrupt Status
Register (05H)
Bits 7:0 (Hex)
20
18
18
Explanation
Arbitration steps completed. Selection time-out occurred then disconnected
Selection with
ATN3
steps fully executed
Sequence halted during command transfer due to premature phase change;
some CDB bytes may not have been sent; check FIFO flags
One, two, or three message bytes sent; sequence halted because Target failed
to assert command phase after third message byte, or prematurely released
message out phase;
ATN
released only if third message byte was sent
Arbitration and selection completed; sequence halted because Target failed to
assert message out phase;
ATN
still driven by ESC
2
18
0
18
Initiator Select with
ATN
and Stop Steps
Internal State
Interrupt Status
Register (06H)
Register (05H)
Bits 2:0 (Hex)
Bits 7:0 (Hex)
0
0
Explanation
20
18
Arbitration steps completed. Selection time-out occurred then disconnected
Arbitration and selection completed; sequence halted because Target failed to
assert message out phase;
ATN
still asserted by ESC
Message out completed; one message byte sent;
ATN
on
1
18