dump_spi_flash
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| dump_spi_flash [2021/04/15 11:06] – [J-Link] kingkevin | dump_spi_flash [2021/04/15 11:11] – [interface] kingkevin | ||
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| * nWP: active low write protect. Set it low if you only intend to read out the flash and don't want to accidentally erase data. Set it high if you want to write it | * nWP: active low write protect. Set it low if you only intend to read out the flash and don't want to accidentally erase data. Set it high if you want to write it | ||
| * CLK: clock line with clock polarity: idle low, and clock phase: sample data on rising edge. Since SPI is a synchronous protocol, the data traffic is synchronized to this clock, provided by the master (your programmer). This allows you to set the frequency: very low for more reliable traffic (there is not lower limit), or very high for fast transfer (often up to 100 MHz). The clock also does not need to be periodic (allowing sloppy big-banging implementation) and the edge time not strict (allowing any voltage shifter technology) | * CLK: clock line with clock polarity: idle low, and clock phase: sample data on rising edge. Since SPI is a synchronous protocol, the data traffic is synchronized to this clock, provided by the master (your programmer). This allows you to set the frequency: very low for more reliable traffic (there is not lower limit), or very high for fast transfer (often up to 100 MHz). The clock also does not need to be periodic (allowing sloppy big-banging implementation) and the edge time not strict (allowing any voltage shifter technology) | ||
| + | * nCS: chip select line, active low. You must set it low to start a new transaction. It also allows to have multiple flash chips (SPI slaves) on the same data lines (you then just select the one you want to talk too) | ||
| * MOSI/DI: master output slave input (flash chip data input). You will send the commands on this pin | * MOSI/DI: master output slave input (flash chip data input). You will send the commands on this pin | ||
| * MISO/DO: master input slave output (flash chip data output). You will receive the replies and data on this pin | * MISO/DO: master input slave output (flash chip data output). You will receive the replies and data on this pin | ||
dump_spi_flash.txt · Last modified: 2024/01/07 17:49 by 127.0.0.1