LM/IM v5.1

LM/IM v5.0

Switched to National PLL, added "mode 6" compatibility and digital subsonic filter.

LM/IM v4.1

Improved high frequency response in IFB mode.

LM/IM v3.0

Same as 2.5, but for rev D-F boards. Last version for older PIC16LF877A processor.

LM/IM v4.0

Switched to PIC18LF452 processor (and added IFB emulation mode.