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8019AS.doc
2001-05-10
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SPECIFICATION
RTL8019AS
34
6.2.3. Plug and Play Isolation Sequence
The Plug and Play isolation sequence is divided into four states: Wait for Key, Sleep, Isolation,
and Config states. The state transitions for the Plug and Play ISA card are shown below.
Power up
RSTDRV or
Reset command
Wait for Key
State
Active Commands
no active
commands
Sleep
State
Active Commands
Reset
Reset CSN
Wait for Key
Wake [CSN]
Isolation
State
Active Commands
Reset
Reset CSN
Wait for Key
Set RD_DATA Port
Serial isolation
Wake [CSN]
Set CSN
Config
State
Active Commands
Reset
Reset CSN
Wait for Key
Wake [CSN]
Resource Data
Status
Logical Device
I/O Range Check
Activate
Configuration Registers
Set CSN
(WAKE=0) AND (CSN=0)
(WAKE<>0) AND (WAKE=CSN)
Lose serial isolation OR
(WAKE<>CSN)
WAKE<>CSN
NOTES:
1. CSN= Card Select Number
2. RSTDRV causes a state transition
from the current state to Wait for Key and sets all CSNs to zero
Set CSN=0
initiation key
3. The Wait for Key command causes a state transition from the
current state to Wait for Key
4. The Reset CSN commands include PnP Reset CSN and RT Reset CSN commands.
The former sets all ISA PnP cards' CSNs to zero while the latter only sets RTL8019
PnP cards' CSNs to zero. Both commands do not cause a state transition.
Figure 4. Plug and Play ISA Card State Transitions