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in case someone is interested in that i have noticed that at address 03 you can see when the fuel pump prime just before you start the engine

02 is the value at that address when the fuel pump prime
00 is the value afther the fuel pump finished to prime

binary:
0000 0010 = 02
0000 0000 = 00

Hey thats cool, so Nistune Type 1 can trace RAM variables lower than 0040, or in other words, the internal registers of the 6303.

Normal consult doesnt do that!

What you have found there is that the fuel pump control is bit 1 of Port 2 (p21) of the 6303.

This is pin 11 of the hd6303ycp (plcc 68 ), which should be connected to fuel pump control ground through a transistor.

Being able to trace the internal registers would make things a little easier during continued reverse-engineering. You might want to also check out port 5 (0015) and port 6 (0017). These should be the main ports controlling most of the general output switching (emissions equip, led's, etc.)

RAM trace was a must in helping with finding the registers used on Type 1 boards. It can also be used on Type2-4 boards using Extended Consult

Regular consult can RAM trace also but is restricted to what the ECU lets you see