Re: [U-Boot-Users] How do you test a bit set/clear from U-Boot command line/script?
Wolfgang Denk wrote:
In message 444FD06D.4060309@orkun.us you wrote:
Within a u-boot script (to be executed by autoscr command), I need to read a GPIO port and if a particular GPIO bit is set execute some conditional commands. I am not sure how to do this with test/itest commands. Any ideas?
This is obviously highly hardware specific.
I am not asking anything about hardware. Forget I said GPIO. Let's say a value in general memory space. It could be in ram or flash....
I know I can compare a simple value using itest command. e.g.
itest *4000 -eq 1234 && echo 'Addr 4000 contains 1234'
Now my problem is how can I test a bit of 32 bit quantity (say bit 4) stored at location 4000? This is a question about general hush/u-boot shell capability? It is a generic question...
Best regards, Tolunay
In message 444FDD08.2010101@orkun.us you wrote:
I am not asking anything about hardware. Forget I said GPIO. Let's say a value in general memory space. It could be in ram or flash....
I know I can compare a simple value using itest command. e.g.
itest *4000 -eq 1234 && echo 'Addr 4000 contains 1234'
Now my problem is how can I test a bit of 32 bit quantity (say bit 4) stored at location 4000? This is a question about general hush/u-boot shell capability? It is a generic question...
At the moment there is no command that implements this. As you probaly are aware, the "itest" command just implements the following operations:
op_tbl_t op_table [] = { { "-lt", LT }, { "<" , LT }, { "-gt", GT }, { ">" , GT }, { "-eq", EQ }, { "==" , EQ }, { "-ne", NE }, { "!=" , NE }, { "<>" , NE }, { "-ge", GE }, { ">=" , GE }, { "-le", LE }, { "<=" , LE }, };
Feel free to add new commands for AND, OR, and XOR...
Best regards,
Wolfgang Denk
participants (2)
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Tolunay Orkun -
Wolfgang Denk