SDI clock control register (SDIO_CLKCR)
| CLKDIV | Clock divide factor |
| CLKEN | Clock enable bit |
| PWRSAV | Power saving configuration bit |
| BYPASS | Clock divider bypass enable bit |
| WIDBUS | Wide bus mode enable bit |
| NEGEDGE | SDIO_CK dephasing selection bit |
| HWFC_EN | HW Flow Control enable |