如何设置64位寄存器字段中的第45位？
我试图使用 C 设置 64 位宽的寄存器中的第 46 位。我该如何设置该位？
目前我正在这样做：
uint32_t= address ;
uint64_t data =1ULL << 46;
打印这表明位 14 正在设置。我无法设置甚至位 32。如果我设置位 32，它将设置位 0。33 将设置位 1。看起来它正在进行循环移位0-31 后再次从 0 开始。
以 64 位宽注册。
知道我该如何设置这个位吗？
例如：
reg_addr.val = FEATURE_REG;
printf(stdout, "Programming enable at address %x=%llx\n",
reg_addr.val,reg_addr.val);
data.val = (1ULL << 46);
printf("Data value %llx\n",data.val);}
I was trying to set 46th bit in a register which of 64 bits wide using C.How do i go about setting this bit ?
Currently i am doing this:
uint32_t= address ;
uint64_t data =1ULL << 46;
Printing this is showing that bit 14 is getting set.I am not able to set even bit 32. If i set bit 32 it sets bit 0. 33 will set bit 1. Looks like it is doing circular shifting after 0-31 again it starts over with 0.
Register in 64 bit wide.
Any idea how do i go about setting this bit ?
Eg:
reg_addr.val = FEATURE_REG;
printf(stdout, "Programming enable at address %x=%llx\n",
reg_addr.val,reg_addr.val);
data.val = (1ULL << 46);
printf("Data value %llx\n",data.val);}
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如果您使用 uint32_t 或 uint64_t 类型，则正确打印是通过以下方式完成的：
假设 reg_addr.addr 的类型为 uint32_t，类型 reg_addr.val 的类型为 uint64_t。
If you use types as uint32_t or uint64_t printing correctly is done with:
assuming reg_addr.addr is of type uint32_t and type reg_addr.val is of uint64_t.
你的代码是正确的。
您应该检查您的平台是否正确支持 64 位整数类型：
should print
如果是这种情况，则错误可能（如 @pmg 在评论中提到的）在于您检查该位是否设置的方式。
在新的编辑中，您提到它是一个寄存器。由于其易失性属性，IO 寄存器可能具有特殊行为。我建议你首先检查一下用普通物体设置一点。
Your code is correct.
You should check that 64-bit integer types are correctly supported in your platform:
should print
If this is the case, the error is probably (as mentioned by @pmg in the comments) in how you check if the bit is set.
In the new edit, you mentioned it is a register. IO registers can have special behavior due to their volatile property. I suggest you to first check to set a bit with a normal object.
我希望您不要检查该行的输出来得出移位未正确完成的结论！？
将 64 位值两次传递给 printf，但使用 %x（可能是 32 位）和 %llx（64 位）来输出值将不起作用。我猜你的意思是在第一个参数处获取 reg_addr.val 的地址！？
I hope you do not check the output of this line to conclude the shifting is not done correctly!?
Passing the 64 bit value two times to
printf, but using %x (probably 32 bit) and %llx (64 bit) to output the values will not work. I guess you meant to take the address of reg_addr.val at the first parameter!?