ADSP-BF537 Blackfin Processor Hardware Reference
6-11
External Bus Interface Unit
AMC Description of Operation
The following sections describe the operation of the AMC.
Avoiding Bus Contention
Because the three-stated data bus is shared by multiple devices in a system,
be careful to avoid contention. Contention causes excessive power dissipa-
tion and can lead to device failure. Contention occurs during the time one
device is getting off the bus and another is getting on. If the first device is
slow to three-state and the second device is quick to drive, the devices
contend.
There are two cases where contention can occur. The first case is a read
followed by a write to the same memory space. In this case, the data bus
drivers can potentially contend with those of the memory device addressed
by the read. The second case is back-to-back reads from two different
AWE
O
Asynchronous memory write enable
ARE
O
Asynchronous memory read enable
AOE
O
Asynchronous memory output enable
In most cases, the AOE pin should be connected to the
OE pin of an external memory-mapped asynchronous
device. Please refer to the product data sheet for specific
timing information between the AOE and ARE signals to
determine which interface signal should be used in your
system.
ARDY
I
Asynchronous memory ready response
ABE[1:0]/SDQM[1:0]
O
Byte enables
1 Pin Types: I = Input, O = Output
Table 6-2. Asynchronous Memory Interface Signals (Cont’d)
Pad
Pin Type
1
Description
Summary of Contents for Blackfin ADSP-BF537
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Page 90: ...Development Tools 1 32 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 138: ...Programming Examples 4 26 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 340: ...SDC Programming Examples 6 84 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 606: ...Programming Examples 9 94 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 660: ...Programming Examples 10 54 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 720: ...Electrical Specifications 11 60 ADSP BF537 Blackfin Processor Hardware Reference ...
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Page 938: ...Programming Examples 15 62 ADSP BF537 Blackfin Processor Hardware Reference ...
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Page 986: ...Programming Examples 18 28 ADSP BF537 Blackfin Processor Hardware Reference ...
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Page 1218: ...Index I 56 ADSP BF537 Blackfin Processor Hardware Reference ...