cs4239 Cirrus Logic, Inc., cs4239 Datasheet - Page 20

• Manufacturer Part Number: cs4239
• Description: Crystalclear? Ortable Isa Audio System Logic
• Manufacturer: Cirrus Logic, Inc.

Bypassing Plug and Play
The SLAM method allows the user to bypass the
Plug and Play features and, as an option, allows
the part to act like a non-Plug and Play or legacy
device; however, the SLAM method only sup-
ports one Cirrus ISA Audio IC per system. The
user directly programs the resources into the
part, and then optionally disables the PnP and/or
the Crystal Key, which forces the part to disre-
gard any future PnP or Crystal initiation key
sequences (All activated logical devices appear
as legacy devices to PnP). The Crystal and PnP
keys can also be disabled through the E
The SLAM method uses the Address Port (AP)
similarly to Plug-and-Play. Although the standard
AP is 279h, two other selections are available for
non-standard implementations. See the Address
Port Configuration section for more details.
To use the SLAM method, the following se-
quence must be followed:
20
1. Host sends 32-byte Crystal key to the AP,
2. Host programs CSN (Card Select Number)
3. Host programs the configuration registers of
chip enters configuration mode.
by writing a 06h and 00h to the AP.
each logical device by writing to the AP. The
following data is the maximum amount of in-
formation per device. All current devices only
need a subset of this data:
Logical Device ID (15h, xxh)
I/O Port Base Address 0 (47h, xxh, xxh)
I/O Port Base Address 1 (48h, xxh, xxh)
I/O Port Base Address 2 (42h, xxh, xxh)
xxh is logical device number: 0-5
high byte , low byte
high byte , low byte
high byte , low byte
2
PROM.
The following illustrates typical data sent using
the SLAM method.
4. Repeat #3 for each logical device to be en-
5. Host activates chip by writing a 79h to AP.
6. (Optional) Host disables PnP Key by writing
NOTE: To enable the PnP/Crystal Keys after
abled. (Not all devices need be enabled.)
a 55h to CTRLbase+5. The part will not par-
ticipate in any future PnP cycles. The Crystal
Key can also be disabled by writing a 56h to
CTRLbase+5.
they have been disabled by the SLAM
method, bring the RESDRV pin to a logic
high or remove power from the device.
006h, 001h
015h, 000h
047h, 005h, 034h ; WSSbase = 0x534
048h, 003h, 088h ; SYNbase = 0x388
042h, 002h, 020h ; SBbase = 0x220
022h, 005h
02Ah, 001h
025h, 003h
033h, 001h
015h, 001h
047h, 002h, 000h ; GAMEbase = 0x200
033h, 001h
Interrupt Select 0 (22h, xxh)
Interrupt Select 1 (27h, xxh)
DMA Select 0 (2Ah, xxh)
DMA Select 1 (25h, xxh)
Activate Device (33h, 01h)
(33h, 00h deactivates a device)
CrystalClear Portable ISA Audio System
TM
; CSN=1
; LOGICAL DEVICE 0
; WSS & SB IRQ = 5
; WSS & SB DMA0 = 1
; WSS capture DMA1 = 3
; activate logical device 0
; LOGICAL DEVICE 1
; activate logical device 1
CS4239
DS253PP2