The datasheet lists something like this:

```
[0x01f] EPRXREG
EPRXLock[3:0] = 4'd5;
EPRXReLock[3:0] = 4'd5
```

I understand that it is an 8-bit register at address `0x01f`

, it contains 2 fields and each of them is 4 bits wide (`[3:0]`

and the `4`

in `4'd5`

). But what is `'d5`

?

Other registers have

```
4'd12 1'b0 4'h4 4'hF 7'd32
```

## Best Answer

`4'd5`

indicates afour-bit value, expressed indecimalas5. It's the same as`4'b101`

(101_{2}= 5_{10}).Likewise,

`4'hF`

is a four-bit value indicating`0xF`

in hex; octal may also be seen (e.g.`4'hF`

can also be denoted as`4'o17`

)