PKP
VS1000 P
ROGRAMMER
’
S
G
UIDE
VSMPG
16.6
VS1000 ROM code usage
The ROM code in VS1000 has the following usage for SPI:
At boot-up the SPI chip select is checked: if it’s pulled high, SPI boot is attempted.
When SPI is not active, the default player application uses the SPI data lines (SI and
SO) in GPIO mode as LED controls.
16.7
Effect of Clock Multiplier
Note that the clock multiplier affects SPI speed. In VS1000 ROM you can read the
current clock multiplier setting in global variable
clockX
. Here’s a line of code that sets
the SPI clock speed taking the clock multiplier into account:
PERIP(SPI0_CLKCONFIG) = SPI_CC_CLKDIV * (clockX - 1);
Rev. 0.20
2011-10-04
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