SDC Register Definitions
6-72
ADSP-BF537 Blackfin Processor Hardware Reference
•
Write to precharge delay
(
TWR
)
The
TWR
bits in the SDRAM memory global control register
(
EBIU_SDGCTL
) select the t
WR
value. Any value between 1 and 3
clock cycles may be selected. For example:
•
TWR = 00
Reserved
•
TWR = 01
1 clock cycle
•
TWR = 10
2 clock cycles
•
TWR = 11
3 clock cycles
•
Powerup start delay
(
PUPSD
)
The powerup start delay bit (
PUPSD
) optionally delays the powerup
start sequence for 15
SCLK
cycles. This is useful for multiprocessor
systems sharing an external SDRAM. If the bus has been previously
granted to the other processor before powerup and self-refresh
mode is used when switching bus ownership, then the
PUPSD
bit
can be used to guarantee a sufficient period of inactivity from
self-refresh to the first Precharge command in the powerup
sequence in order to meet the exit self-refresh time (t
XSR
) of the
SDRAM.
•
Powerup sequence mode
(
PSM
)
If the
PSM
bit is set to 1, the SDC command sequence is:
1. Precharge all
2. Mode register set
3. 8 auto-refresh cycles
Summary of Contents for Blackfin ADSP-BF537
Page 42: ...Contents xlii ADSP BF537 Blackfin Processor Hardware Reference ...
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 ...
Page 840: ...Programming Examples 13 42 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 876: ...Programming Examples 14 36 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 938: ...Programming Examples 15 62 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 958: ...Programming Examples 17 12 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 986: ...Programming Examples 18 28 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 1162: ...G 26 ADSP BF537 Blackfin Processor Hardware Reference ...
Page 1218: ...Index I 56 ADSP BF537 Blackfin Processor Hardware Reference ...