406 AMD Geodeā„¢ SC2200 Processor Data Book
Electrical Specifications
32580B
Figure 9-25. PIO Data Transfer to/from Device Timing Diagram
ADDR valid1
WRITE IDE_DATA[15:0]
READ IDE_DATA[15:0]
t0
t1t2t9
t2i
t3
t5
t6z
t6
tA
t4
tCtRD
tBtC
IDE_IOR0#
IDE_IOW0#
IDE_IORDY02,3
IDE_IORDY02,4
IDE_IORDY02,5
Notes:
1) Device address consists of signals IDE_CS[0:1]# and IDE_ADDR[2:0].
2) Negation of IDE_IORDY[0:1] is used to extend the PIO cycle. The determination of whether or not the cycle is to be
extended is made by the host after tA from the assertion of IDE_IOR[0:1]# or IDE_IOW[0:1]#.
3) Device never negates IDE_IORDY[0:1]. Devices keep IDE_IORDY[0:1] released, and no wait is generated.
4) Device negates IDE_IORDY[0:1] before tA but causes IDE_IORDY[0:1] to be asserted before tA. IDE_IORDY[0:1] is
released, and no wait is generated.
5) Device negates IDE_IORDY[0:1] before tA. IDE_IORDY[0:1] is released prior to negation and may be asserted for no
more than 5 ns before release. A wait is generated.
6) The cycle completes after IDE_IORDY[0:1] is reasserted. For cycles where a wait is generated and IDE_IOR[0:1]# is
asserted, the device places read data on IDE_DATA[15:0] for tRD before asserting IDE_IORDY[0:1].