AHB Peripheral Clock enable register (CRM_AHBEN)
| DMA1EN | DMA1 clock enable |
| SRAMEN | SRAM interface clock enable |
| FLASHEN | FLASH clock enable |
| CRCEN | CRC clock enable |
| OTGFS1EN | OTGFS1 clock enable |
| GPIOAEN | I/O port A clock enable |
| GPIOBEN | I/O port B clock enable |
| GPIOCEN | I/O port C clock enable |
| GPIODEN | I/O port D clock enable |
| GPIOFEN | I/O port F clock enable |