EA
EA (EA Prime) is a pin on the MCU that controls whether the MCU runs off Internal ROM or an external ROM chip.
Adapted from pgmfi.org wiki
_EA (EA Prime) is a pin on the MCU that controls whether the MCU runs off Internal ROM or an external ROM chip. _EA is pin 31 on 40-pin Intel8051 MCUs J1 on OBD1 ECUs controls the state of _EA, and is used to activate an external ROM you install.
Credits and source
Authors Anonymous PGMFI contributor
Source Adapted from EA on pgmfi.org wiki. Licensed under CC BY-NC-SA 1.0.