| BFM | Boot Flash Memory | 
| CP | Code Protection | 
| CRC | Cyclic Redundancy Check | 
| ECR | EJTAG Control register | 
| EJTAG | Enhanced Joint Test Action Group | 
| ETAP | Enhanced Tag Access Port | 
| ICSP | In-Circuit Serial Programming | 
| JTAG | Joint Test Action Group | 
| LSb | Least Significant bit | 
| MTAP | Microchip Tag Access Port | 
| MSb | Most Significant bit | 
| PE | Programming Executive | 
| PFM | Program Flash Memory | 
| POR | Power-on Reset | 
| PWP | Program Write Protection | 
| SFRs | Special Function Registers | 
| SPI | Serial Peripheral Interface | 
| TCK | Test Clock | 
| TDI | Test Data Input | 
| TDO | Test Data Output | 
| TMS | Test Mode Select | 
| XferData | Transfer Data | 
| XferFastData | Transfer Fast Data |