1995 Escort LX 1.9 - A/C cycles on and off at regular intervals. Low pressure reading 100 psi. What does it mean that the low pressure reading is so high? Do I need a new compressor, or should I check something else?

High pressure on the low side and normal cycling usually does mean the compressor is worn. Is there a reading for the high side?
If the compressor is at fault, I would also recommend and expansion valve and flush the debris from the entire system.