PIC18F2XK20 Datasheet PDF - Microchip Technology

PROGRAMMING OVERVIEW
   The PIC18F2XK20/4XK20 devices can be programmed using either the high-voltage In-Circuit Serial Programming™ (ICSP™) method or the low-voltage ICSP method. Both methods can be done with the device in the users’ system. The low-voltage ICSP method is slightly different than the high-voltage method and these differences are noted where applicable. This programming specification applies to the PIC18F2XK20/4XK20 devices in all package types.