Control A

Name:
CTRLA
Offset:
0x00
Reset:
0x00
Access:
Configuration Change Protection
Bit76543210
CMD[6:0]
AccessR/WR/WR/WR/WR/WR/WR/W
Reset0000000

Bits 6:0 – CMD[6:0]: Command

Command

Write this bit field to enable or issue a command. The Chip Erase and EEPROM Erase commands start when writing the command. The others enable an erase or write operation. The operation is started by doing a store instruction to an address location.

A change from one command to another should always go through a No command (NOCMD) or No operation (NOOP) command. If attempting written to a programming command (except NOCMD or NOOP) while the Flash or EEPROM is busy, a Command Collision error is signalized in the ERROR bit field in the NVMCTRL.STATUS register.

Value Name Description
0x00 NOCMD No command
0x01 NOOP No operation
0x02 FLWR Flash Write Enable
0x08 FLPER Flash Page Erase Enable
0x09 FLMPER2 Flash 2-page Erase Enable
0x0A FLMPER4 Flash 4-page Erase Enable
0x0B FLMPER8 Flash 8-page Erase Enable
0x0C FLMPER16 Flash 16-page Erase Enable
0x0D FLMPER32 Flash 32-page Erase Enable
0x12 EEWR EEPROM Write Enable
0x13 EEERWR EEPROM Erase and Write Enable
0x18 EEBER EEPROM Byte Erase Enable
0x19 EEMBER2 EEPROM 2-byte Erase Enable
0x1A EEMBER4 EEPROM 4-byte Erase Enable
0x1B EEMBER8 EEPROM 8-byte Erase Enable
0x1C EEMBER16 EEPROM 16-byte Erase Enable
0x1D EEMBER32 EEPROM 32-byte Erase Enable
0x20 CHER Erase Flash and EEPROM. EEPROM is skipped if EESAVE fuse is set. (UPDI access only.)
0x30 EECHER Erase EEPROM
Other - Reserved