DM336P Davicom Semiconductor Incorporated, DM336P Datasheet - Page 18

• Manufacturer Part Number: DM336P
• Manufacturer: Davicom Semiconductor Incorporated

There are two other special considerations for
software protocol. During an iteration, it is possible
that the 55H and AAH combination is never detected.
It is also possible that the checksum does not match.
If either of these cases occurs on the first iteration, it
must be assumed that the READ_DATA port is in
conflict. If a conflict is detected, then the
READ_DATA port will be relocated. The above
process is repeated until a non-conflicting location for
the READ_DATA port is found. The entire range
between 203H and 3FFH is available; however, in
practice, it is expected that only a few locations will be
tried before software determines that no Plug and
Play cards are present.
(8) Plug and Play Isolation Sequence
The Plug and Play isolation sequence is divided into four states: Wait for Key, Sleep, Isolation, and Configuration.
The state transitions for the Plug and Play ISA card are shown below:
18
Note: 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.
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 DM Reset CSN commands.
ISOLATION
The former sets all ISA PnP cards CSNs to zero, while the latter only sets DM6383 PnP cards
CSNs to zero. command will cause a state transition.
STATE
W A K E = 0 & C S N = 0
LOSE SERIAL ISOLATION OR
V.34 Integrated Data/ Fax/Voice/Speakerphone Modem Device Set
Plug and Play ISA Card State Transitions
A C T I V E C O M M A N D S
R E S E T
R E S E T C S N
WAIT FOR KEY
SET RD_DATA PORT
SERIAL ISOLATION
W A K E ( C S N )
SET CSN
W A K E < > C S N
WAIT FOR KEY
STATE
STATE
S L E E P
P O W E R U P
RETDRV OR
R E S E T C O M M A N D
SET CSN
A C T I V E C O M M A N D S
A C T I V E C O M M A N D S
R E S E T
R E S E T C S N
WAIT FOR KEY
W A K E ( C S N )
During subsequent iterations, the occurrence of either
of these two special cases should be interpreted as
the absence of any further Plug and Play cards (i.e.
the last card was found in the previous iteration). This
terminates the isolation protocol.
Note: The software must delay 1 msec prior to
NO ACTIVE
C O M M A N D S
starting the first pair of isolation reads, and wait
250 msec between each sub-sequence pair of
isolation reads. This delay gives the ISA card
time to access information from very slow
storage devices.
W A K E < > C S N
STATE
CONFIG
W A K E < > 0 & W A K E = C S N
R E S E T
R E S E T C S N
WAIT FOR KEY
W A K E ( C S N )
R E S O U R C E D A T A
STATUS
LOGICAL DIVICE
I/O RANGE CHECK
ACTIVATE
CONFIGURATION REGISTERS
A C T I V E C O M M A N D S
Version: DM336P-DS-F02
DM336P
August 15, 2000
Final