External Regeneration Circuit
The APEX drives allow the user to build external regeneration circuits by disabling the Regen Fault when SW1 #1 is turned ON.
The APEX10 has this capability.
This feature was not enabled until Rev G of the firmware for an APEX20 & 40. The first firmware to have this feature for the APEX20 & 40 is 92-013834-01 REV G.