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rule of thumb/ c1 M8 W# x; \/ ?' F0 ^- w
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: i; M# T4 D S- The format of the signed type is two’s complement. 有符号数均为补码表示
- If any operand in an expression is unsigned the operation is considered to be unsigned. 只有计算表达式右边有无符号数，整个计算式都按照无符号数规则运算
- 只有算式右边全为有符号数，运算才会自动补齐所需的bit数，n+n=n+1.n*n=2n
- The value -4 represented as a 3bit signed hex value would be specified as -3’sh4. A decimal number is always signed. verilog2001中用’s来特别声明有符号数，十进制的数都是有符号数
- Type casting using $unsigned will make the operation unsigned. The operand will be sign extended with 0’s if necessary. $usigned()函数在高位补0
- A=$signed(B) will extend using sign bit. $unsigned()函数会在高位补与符号位相同的bit
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basic signed addition8 X) R! F$ {% K% r8 t! l) g* J
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发表于 2019-7-30 15:59
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支持！
反对！