Hello mpgmike,

thanks for your offer.

I decided to use two PICs because Iīm too dumb to program everything correct to do the project with one PIC.
Reason is I began setting footsteps into the PIC world about 10 years ago,"developed" a small singlesided one PIC16F88
board and ordered about 30 of them from a PCB Professional. Now I had a small board to use for simple tasks
like controlling an electric waterpump and switching a cooling fan and showing Temperature and pump load on an LCD.The code was primitive AND very slow, the PIC ran on 4 MHz but for temperature control it was ok. Was lucky with that then.
Paused several years and began a project for one of the cars of my wife with a controller that added an electric fuel
pump. Now problems began because I needed two HPWM outputs.Not possible with a 16F88. I had some simple thingys worked out with a 18F1320 and at the time I had established the right configs (with the help of this community) I wiped the sweat off my forehead and could do the same the 16F88 could but way faster.
Serial communication didnīt work because of a problem in my homecomputer setup. Strange thing because I posted
forum threads 8-10 years ago that showed serial com worked but now without changing the homecomputer or the software it didnīt anymore.
So I purchased PBP3 Gold two month ago , set it up on my notebook and voila, serial com between PICs worked again.
I decided to take two PICs , one for the slower Temperature control (16F88) and one 18F1320 for the faster fuel pump
control. I dont want to run the fuel pump full load all the time because it draws more than 20 Amps.And it costs more than 300$ so I want to save it. Minimum load (plus a reserve) at engine idle and quick response to raising engine speed. Nowadays the cool guys control these pumps via a digital fuel pressure controller that sends a signal about the amount of return fuel, but these units cost about 500 $ and need a controller too (300$).
With two PICs I can use my simple code concentrating on the single task , only the 18F1320 has to run the LCD too.
HA! the "professional" pump controllers use LEDs and no LCD.
here an example for a waterpump controller:

https://www.tecomotive.com/en/products/tinycwa.html

I use a "huge" billet aluminium case, a LCD and military style connectors capable of 40 AMPS.

My problem: the communication of these two PICs and the LCD routine are slowing the 18F1320 down to
uselessness.One mainprogram cycle may take 0.3 seconds. that 3 times more than the acceptable limit.
Because when the engine revs up the fuel pump has to rev up too.Fast.otherwise the egine will bog.
With Henriks help we have pinned it down the problem that the 18F1320 has to wait for the 16F88 to send
a Character. The 16F88 has a slow routine wich slows down the 18F as well.
So the communication between both shouldnīt disturb the 18Fs main routine. Now I have to separate
the "count/HPWM" main routine from the "get charakters and show on LCD" routine. because the LCD routine
can take a whole second or some more, that doesnīt matter.
I appreciate your help.
Next point: Iīm somewhat happy getting the serial com between both pics running......old fart thing sort of.