communication configuration register
| IMODE | Instruction mode |
| IDTR | Instruction double transfer rate |
| ISIZE | Instruction size |
| ADMODE | Address mode |
| ADDTR | Address double transfer rate |
| ADSIZE | Address size |
| ABMODE | Alternate byte mode |
| ABDTR | Alternate bytes double transfer rate |
| ABSIZE | Alternate bytes size |
| DMODE | Data mode |
| DDTR | Alternate bytes double transfer rate |
| DQSE | DQS enable |
| SIOO | Send instruction only once mode |