82091AA Datasheet, PDF (43/204 Pages) Intel Corporation – ADVANCED INTEGRATED PERIPHERAL (AIP)

82091AA
Bit
Description
7 MIDI CLOCK FOR SERIAL PORT A ENABLE (SAMIDI) When SAMIDI^e1 the clock into Serial
Port A is changed from 1 8462 MHz–2 MHz The 2 MHz clock is needed to generate the MIDI baud
rate When SAMIDI^e0 the clock frequency is 1 8462 MHz
6 5 RESERVED
4 SERIAL PORT A IRQ SELECT (SAIRQSEL) When SAIRQSEL^e0 IRQ3 is selected for the Serial
Port A interrupt When SAIRQSEL^e1 IRQ4 is selected for the Serial Port A interrupt This bit can be
configured by strapping options at powerup for HWB and HWE modes only For SWMB and SWAI
hardware configuration modes the default is 0 (IRQ3) Note that while the default address and IRQ
assignments for SWMB and SWAI modes are the same for both serial ports the serial ports are
disabled and programming of this register is required for operation
3 1 SERIAL PORT A ADDRESS SELECT (SAADS) This field selects the ISA address range for Serial
Port A as follows
Bits 3 1
000
001
010
011
100
101
110
111
ISA Address Range
3F8 – 3FFh
2F8 – 2FFh
220 – 227h
228 – 22Fh
238 – 23Fh
2E8 – 2EFh
338 – 33Fh
3E8 – 3EFh
This field can be configured by strapping options at powerup for HWB and HWE modes only For
SWMB and SWAI hardware configuration modes the default is 000 (3F8 – 3FFh) Note that while
the default address and IRQ assignments for SWMB and SWAI modes are the same for both serial
ports the serial ports are disabled and programming of this register is required for operation
0 SERIAL PORT A ENABLE (SAEN) When SAEN^e1 Serial Port A is enabled When SAEN^e0
Serial Port A is disabled This bit can be configured by strapping options at powerup for HWB and
HWE modes only For SWMB and SWAI hardware configuration modes the default is 0 (disabled)
4 1 11 SACFG2 SERIAL PORT A POWER MANAGEMENT AND STATUS REGISTER
Index Address
Default Value
Attribute
Size
31h
RRR0 00U0
Read Write
8 bits
This register enables disables the Serial Port A module auto powerdown and can place the module into a
direct powerdown mode The register also provides Serial Port A idle status resets the Serial Port A module
and places Serial Port A into test mode
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