Fuel Pump Prime

Looking to come up with a logic that will allow me to prime the fuel pump if ign is in run and fuel pump is active. I want it to prime until desired fuel pressure is reached and then reset until after a start attempt. If engine is running I currently want this fuel pump to be on 100%. The ECU monitors FP and sends it via CAN.

would the logic be

On if

keypadfuelpump = true

and

keypadign = true

and

fuelpressure < 350kpa

and

engineRPM < 400

or

keypadfuelpump = true

and

keypadign = true

and

engineRPM > 500

possibly add a hysteresis of 100kpa as the ECU compensates for FP so it would still do its proper cold start even a little low on FP.