Hello,
we noticed for one of our boards that the nRF9160 is not able to startup with a floating MISO pin on the SPI where the flash is configured in device tree (SPI1 / P0.12).
Although we only made some tests with a not fully populated board with a software were the pin is included (yes, it should be removed completely if not used), we would still like to understand the problem to avoid similar problems in production, since our understanding is that this should just cause an error message.
We have tested with SDK 2.5.2
flash_spi: &spi1 {
compatible = "nordic,nrf-spim";
status = "okay";
pinctrl-0 = <&spi1_default_alt>;
pinctrl-1 = <&spi1_sleep_alt>;
pinctrl-names = "default", "sleep";
cs-gpios = <&gpio0 25 GPIO_ACTIVE_LOW>;
mx25r64: mx25r6435f@0 {
compatible = "jedec,spi-nor";
reg = <0>;
spi-max-frequency = <80000000>;
label = "MX25R64";
jedec-id = [c2 28 17];
size = <67108864>; // 0x4000000
};
};
&pinctrl {
spi1_default_alt: spi1_default_alt {
group1 {
psels = <NRF_PSEL(SPIM_SCK, 0, 13)>,
<NRF_PSEL(SPIM_MOSI, 0, 11)>,
<NRF_PSEL(SPIM_MISO, 0, 12)>;
};
};
spi1_sleep_alt: spi1_sleep_alt {
group1 {
psels = <NRF_PSEL(SPIM_SCK, 0, 13)>,
<NRF_PSEL(SPIM_MOSI, 0, 11)>,
<NRF_PSEL(SPIM_MISO, 0, 12)>;
low-power-enable;
};
};
Thank you!
Best regards,
Bernhard
