C/Direct memory access
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m (Created page with 'This example shows how to access memory locations directly (in this case a 16-bit register) <source lang="c"> unsigned short *p; unsigned short mask = 0x400; p = 0xFFFE3A02; if …') |
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| + | From within the kernel, use <code>ptr = ioremap(addr,len)</code> and <code>iounmap(ptr)</code> | ||
Latest revision as of 17:07, 14 February 2013
This example shows how to access memory locations directly (in this case a 16-bit register)
unsigned short *p; unsigned short mask = 0x400; p = 0xFFFE3A02; if (*p & mask) { *p &= ~mask; } else { *p |= mask; }
From within the kernel, use ptr = ioremap(addr,len) and iounmap(ptr)
