In the lab, I'm trying to program the SPI flash from external SPI module but found SPI_CS0 can't be driven low. It seems it's caused by bus contention. On this bus, there are only P1010 SPI, SPI Flash and header for external programming. HRESET on P1010 is asserted prior to turn on the external SPI bus. My question is what the state of SPI_CS0 when HRESET? is it supposed to be input, tristate or output?
The P1010 GUTS_PMUXCR1[SPI] field provides pin assignment for SPI. This register assigns the SPI_CS_B[0]/GPIO[9] to SPI if the P1010 HRESET is asserted.
The SPI_CS_B[0] is output signal.
It looks like that you can use I2C boot sequencer for configuring the GUTS_PMUXCR1 register for assigning the SPI_CS_B[0]/GPIO[9] as GPIO.
The P1010 boot sequencer also can be used for loading simple loop program. The P1010 can execute this loop code during SPI Flash programming using external SPI.
Have a great day,
Pavel
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Hi Pavel,
How about SPI CLK and MOSI pins? are they also output when HRESET asserted?
The P1010 SPI CLK and MOSI pins are outputs if the HRESET is asserted.
Have a great day,
Pavel
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