ADSP-BF50x Blackfin Processor Hardware Reference
5-7
External Bus Interface Unit
One case where contention can occur is a read followed by a write to the
same memory space. In this case, the data bus drivers can potentially con-
tend with those of the memory device addressed by the read.
To avoid contention, program the turnaround time (bank transition time)
appropriately in the asynchronous memory bank control registers. This
feature allows software to set the number of clock cycles between these
types of accesses on a bank-by-bank basis. Minimally, the EBIU provides
one cycle for the transition to occur.
AMC Programming Model
The asynchronous memory global control register (
EBIU_AMGCTL
) config-
ures global aspects of the controller. It contains bank enables and other
information as described in this section. This register should not be
programmed while the AMC is in use. The
EBIU_AMGCTL
register should be
the last control register written to when configuring the processor to
access external memory-mapped asynchronous devices.
The AMC interface is used to access the internal flash memory on
ADSP-BF50x processors containing a flash. For more information,
see
“Internal Flash Memory” on page 6-1
.
Additional information for the
EBIU_AMGCTL
register bits includes:
• Asynchronous memory clock enable (AMCKEN)
The external clock signal (
CLKOUT
), which is an inverted version of
the system clock signal SCLK, can be enabled by setting the
AMCKEN
bit in the
EBIU_AMGCTL
register. In systems that do not use
CLKOUT
,
set the
AMCKEN
bit to 0.
Summary of Contents for EZ-KIT Lite ADSP-BF506F
Page 50: ...Contents l ADSP BF50x Blackfin Processor Hardware Reference ...
Page 92: ...Development Tools 1 30 ADSP BF50x Blackfin Processor Hardware Reference ...
Page 110: ...Interface Overview 3 12 ADSP BF50x Blackfin Processor Hardware Reference ...
Page 236: ...Internal Flash Memory Control Registers 6 92 ADSP BF50x Blackfin Processor Hardware Reference ...
Page 650: ...Programming Examples 15 56 ADSP BF50x Blackfin Processor Hardware Reference ...
Page 804: ...Programming Examples 17 92 ADSP BF50x Blackfin Processor Hardware Reference ...
Page 1194: ...Programming Examples 24 90 ADSP BF50x Blackfin Processor Hardware Reference ...
Page 1256: ...ACM Registers A 50 ADSP BF50x Blackfin Processor Hardware Reference ...
Page 1264: ...Boundary Scan Architecture B 8 ADSP BF50x Blackfin Processor Hardware Reference ...