Issue with volumetric extrusion and power-down safe state

[timschneider]

Hi there,

i found a problem with the current power down safe state with volumetric extrusion enabled in RRF 3.0 on Duet2 ethernet.

current implementation will create an output similiar to the following

; File "0:/gcodes/3DBenchy.gcode" resume print after power failure at 2020-01-11 17:53
G21
M140 P0 S65.0
T-1 P0
G92 X367.515 Y204.243 Z10.700
G60 S1
G10 P0 S220 R220
T0 P0
M98 P"resurrect-prologue.g"
M116
M290 X0.000 Y0.000 Z0.000 R0
T-1 P0
T0 P6
; Workplace coordinates
G10 L2 P1 X0.00 Y0.00 Z0.00
G10 L2 P2 X0.00 Y0.00 Z0.00
G10 L2 P3 X0.00 Y0.00 Z0.00
G10 L2 P4 X0.00 Y0.00 Z0.00
G10 L2 P5 X0.00 Y0.00 Z0.00
G10 L2 P6 X0.00 Y0.00 Z0.00
G10 L2 P7 X0.00 Y0.00 Z0.00
G10 L2 P8 X0.00 Y0.00 Z0.00
G10 L2 P9 X0.00 Y0.00 Z0.00
G54
M200 D0.155
M106 S0.86
M106 P0 S0.86
M106 P2 S0.00
M116
G92 E0.00000
M83
M23 "0:/gcodes/3DBenchy.gcode"
M26 S559573
G0 F6000 Z12.700
G0 F6000 X367.515 Y204.243
G0 F6000 Z10.700
G1 F2520.0 P0
G21
M24

Where M200 is 0.155, which is equal to the internal factor but not the filament diameter.

The line of code from github :

buf.catf("%c%.03f", c, (double)volumetricExtrusionFactors[i]);

which should be

buf.catf("%c%.03f", c, (double)(2.0/sqrtf(volumetricExtrusionFactors[i] * Pi)));

Hope this will help you in fixing it.

Tim