82378ZB Datasheet, PDF (115/137 Pages) Intel Corporation – SYSTEM I/O APIC(SIO.A) AND

E
82378ZB (SIO) AND 82379 (SIO.A)
Utility Bus accesses by the SIO/SIO.A, by an ISA master, and by the DMA are shown in Figure 15 and
Figure 16. UBUSOE# and UBUSTR are driven differently for DMA cycles as shown in Figure 16.
BALE
SA [16:0],
LA[23:17],SBHE#
IOR#,IOW#
SD[7:0] R
SD[7:0] W
ECSADDR[2:0]
ECSEN#
UBUSOE#
UBUSTR
UBUSOE#
U-Bus Access Cycle (SIO as Master)
UBUSTR
ECSEN#
RTCALE#
U-Bus Access Cycle (ISA Master)
RTCALE
U-Bus Access, 8-Bit I/O, RTCALE Cycle
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Figure 15. Utility Bus Access (SIO/SIO.A and ISA Master)
DACK2#
UBUSOE#
UBUSTR
DACK0,1,3,5,6,7#
UBUSOE#
UBUSTR
Figure 16. Utility Bus Access (DMA)
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