G-code starting coordinate ?

Guys,

I tried to find where the starting coordinate of my object ,
Here's the code I've been reading ...

M107
M190 S55 ; set bed temperature
M104 S200 ; set temperature
G28 ; home all axes
G1 Z5 F5000 ; lift nozzle

M109 S200 ; wait for temperature to be reached
G21 ; set units to millimeters
G90 ; use absolute coordinates
M82 ; use absolute distances for extrusion
G92 E0
G1 Z0.200 F7800.000
G1 E-2.00000 F2400.00000
G92 E0
G1 X77.958 Y99.909 F7800.000 <=== is it the starting X,Y coordinate ?

What does it mean by F7800.000 ?

I have a 5cm kapton tape, so I must put it precisely, otherwise the nozzle will hit the edge and make the tape folding...
How to avoid folding tape? Can I adjust the Z limiter for it ?

Thanks

Edited 3 time(s). Last edit at 11/09/2015 03:52PM by bianchi.

yes, well it the end of the first move, so start of your object.

Starting point is alway 0,0 as set when you home your printer (or power on position, if you dont home)

and F is the feedrate (speed of the move * 60) so F7800.000 = 130mm/s
This is just a request though, it limited by your max feedrate in firmware.

Edited 2 time(s). Last edit at 11/09/2015 05:20PM by Dust.