Digi NS9215 - Manual (Page 438)

S E R I A L C O N T R O L M O D U L E : S P I
System boot-over-SPI operation
438 Hardware Reference NS9215
Time to
completion
The boot-over-SPI operation is performed in two steps.
In the first step, the hardware fetches the 16-byte header. The data rate for
this step is about 375 Kbps and completes in less than 0.5ms.
In the second step, the hardware fetches the image at the user-specified data
rate. Calculate time to completion for this step as shown:
Time(s) = (1 / data_rate) * IMAGE
SIZE
For example, with a 20 Mbps data rate and a 256 KB (2Mb) image, the time
to completion is approximately 105ms.
0x14 DynamicRefresh See the Memory Controller chapter.
For example, the value of this entry is 0x00000025 given
a 74.9 MHz AHB clock and a 7.8125μs refresh period.
Ox18 DynamicReadConfig See the Memory Controller chapter.
0x1c DynamictRP See the Memory Controller chapter
Ox20 DynamictRAS See the Memory Controller chapter
Ox24 DynamictSREX See the Memory Controller chapter
Ox28 DynamictAPR See the Memory Controller chapter
Ox2c DynamictDAL See the Memory Controller chapter
Ox30 DynamictWR See the Memory Controller chapter
Ox34 DynamictRC See the Memory Controller chapter
Ox38 DynamictRFC See the Memory Controller chapter
Ox3c DynamictXSRt See the Memory Controller chapter
Ox40 DynamictRRD See the Memory Controller chapter
Ox44 DynamictMRD See the Memory Controller chapter
Ox48 DynamictConfig0 See the Memory Controller chapter.
Field B (buffer enable, in the DynamicConfig0 register)
should be set to 0 (buffers disabled). The buffers will be
enabled by hardware as part of the boot process.
Ox4c DynamictRasCas0 See the Memory Controller Chapter
Ox50-
Ox7c Reserved
Ox80 Boot Code First 4 bytes of boot code
Entry Name Description