AMD-K6-2E/400AFR AMD [Advanced Micro Devices], AMD-K6-2E/400AFR Datasheet - Page 165

• Manufacturer Part Number: AMD-K6-2E/400AFR
• Manufacturer: AMD [Advanced Micro Devices]

22529B/0—January 2000
Misaligned I/O Read
and Write
Figure 57. Misaligned I/O Transfer
Chapter 6
BE[7:0]#
D[63:0]
A[31:3]
BRDY#
M/IO#
SCYC
ADS#
W/R#
D/C#
CLK
ADDR DATA DATA IDLE ADDR DATA DATA IDLE ADDR DATA
Misaligned I/O Read
Table 26 shows the misaligned I/O read and write cycle order
executed by the AMD-K6-2E processor. In Figure 57, the
least-significant bytes (LSBs) are transferred first. Immediately
after the processor samples BRDY# asserted, it drives the
second bus cycle to transfer the most-significant bytes (MSBs)
to complete the misaligned bus cycle.
Table 26. Bus-Cycle Order During Misaligned I/O Transfers
LSB
Type of Access
I/O Write
I/O Read
MSB
Bus Cycles
First Cycle
LSBs
LSBs
DATA
DATA
LSB
AMD-K6™-2E Processor Data Sheet
IDLE ADDR DATA
Misaligned I/O Write
Second Cycle
MSBs
MSBs
DATA
DATA
MSB
IDLE
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