Module regs
- Cr
- Control register
- Dinr
- Data input register
- Doutr
- Data output register
- Icr
- Interrupt clear register
- Ier
- Interrupt enable register
- Isr
- Interrupt status register
- Ivr
- Initialization vector register
- Keyr
- Key register
- Sr
- Status register
- Suspr
- Suspend register