The chip select pin to the flash is strange to me ... The cs at the pin seems to only go down to 3.15V, but after the 1k resistor it goes to 0v when the button is pressed. One would think the cs pin should be connected in between the resistor and button to pull it low.
Code:
FLASH RP2040.-------. || __ | || CS |-----.--------| QSPI_SS| | .|. |`-------' |_| 1K | | O |-. O |-' "BOOTSEL" _|_When QSPI_SS is an input with an internal pull-up resistor enabled, QSPI_SS input will read as high when the BOOTSEL button is not pushed, low when it is - BOOTSEL button reading mode.
In BOOTSEL button reading mode the CS will reflect the button push state but that doesn't matter because the Flash chip is not being interacted with except in normal execution mode.
Statistics: Posted by hippy — Fri Feb 23, 2024 11:47 am