added VCN320 ball bearing option

.gitmodules

 [submodule "firmware/fatfs"]
 	path = firmware/fatfs
 	url = https://github.com/abbrev/fatfs
+[submodule "hardware/BOSL2"]
+	path = hardware/BOSL2
+	url = https://github.com/revarbat/BOSL2.git

hardware/BOSL2

+Subproject commit d700884482dd0eab5aafa17984481b7622522214

hardware/trackball.scad

  *
  * See <http://www.gnu.org/licenses/>.
  */
+include <BOSL2/std.scad>;
+include <BOSL2/threading.scad>;
 
 // https://www.thingiverse.com/thing:421524
 use <external/cherry_mx.scad>
 use_external_pico_model = true;
 draw_keycap = false;
 
+holdertype="ball_rollen";
+//holdertype="static";
 // #######################
 // ## Raspberry Pi Pico ##
 // #######################
 grub_channel_dia = 4.0;
 
 roller_thread_dia = roller_dia + 5.0;
-roller_h = roller_dia + 7.0;
+roller_h = roller_dia + 7.0+2;
 roller_ball_h_off = 0.4;
 roller_ball_hold_off = 0.5;
 roller_thread_hole = roller_dia - 1;
 }
 
 module roller_holder() {
-    translate([0, 0, -roller_h + roller_dia / 2])
-    difference() {
-        color("magenta")
-        union() {
-            translate([0, 0,  roller_h-roller_dia/2 + roller_ball_h_off-3])
-            cylinder(d1 = roller_mount_dia, d2=roller_dia+1,  h = 3);
+    if(holdertype=="static") {
+        translate([0, 0, -roller_h + roller_dia / 2])
+        difference() {
+            color("magenta")
+            union() {
+                translate([0, 0,  roller_h-roller_dia/2 + roller_ball_h_off-3])
+                cylinder(d1 = roller_mount_dia, d2=roller_dia+1,  h = 3);
+                
+                cylinder(d = roller_mount_dia, h = roller_h-roller_dia/2 + roller_ball_h_off-3);
+            }
             
-            cylinder(d = roller_mount_dia, h = roller_h-roller_dia/2 + roller_ball_h_off-3);
-        }
+            translate([-roller_mount_dia / 2 - 1, roller_mount_dia / 2 - roller_holder_sider_cut, -1])
+            cube([roller_mount_dia + 2, roller_mount_dia / 2 + 1, roller_h + 2]);
+            
+            translate([0, 0, -$e])
+            cylinder(d = roller_thread_hole, h = $e+ roller_h - roller_dia / 2 + roller_ball_h_off + roller_ball_hold_off);
         
-        translate([-roller_mount_dia / 2 - 1, roller_mount_dia / 2 - roller_holder_sider_cut, -1])
-        cube([roller_mount_dia + 2, roller_mount_dia / 2 + 1, roller_h + 2]);
+            translate([0, 0, roller_h - roller_dia / 2 + roller_holder_h_compensation])
+            sphere(d = roller_dia, $fn = $fn);
+
+            if (cut_roller_holder)
+            translate([-roller_thread_dia / 2 - 1, -roller_thread_dia, -$e])
+            cube([roller_thread_dia + 2, roller_thread_dia, roller_h + 2]);
+        }
         
-        translate([0, 0, -$e])
-        cylinder(d = roller_thread_hole, h = $e+ roller_h - roller_dia / 2 + roller_ball_h_off + roller_ball_hold_off);
-    
-        translate([0, 0, roller_h - roller_dia / 2 + roller_holder_h_compensation])
+        %color("blue")
         sphere(d = roller_dia, $fn = $fn);
+    }
+    if(holdertype=="ball_rollen") {
 
-        if (cut_roller_holder)
-        translate([-roller_thread_dia / 2 - 1, -roller_thread_dia, -1])
-        cube([roller_thread_dia + 2, roller_thread_dia, roller_h + 2]);
+        l=10;
+        
+        difference() {
+            union() {
+                translate([0,0,$e -l +roller_dia/2 -2])
+                cylinder(d=roller_mount_dia,h=l-1);
+                
+                %union(){
+                color("red")
+                translate([0,0,(roller_dia-3.18)/2])
+                sphere(d = 3.18, $fn = $fn);
+                
+                color("silver")
+                translate([0,0,-1.2+(3.18)/2-0.9])
+                cylinder(d2 = 3.5,d1 = 6,h=1);
+                
+                translate([0,0,-l/2 +roller_dia/2 -2])
+                threaded_rod(d=6, l=l, pitch=1.0);
+                }
+            }
+            
+            translate([0,0,$e -l/2 +roller_dia/2 -2])
+            threaded_rod(d=6.1, l=l, pitch=1.0);
+            
+            if (cut_roller_holder)
+            translate([-roller_thread_dia / 2 - 1, -roller_thread_dia, -l*2])
+            cube([roller_thread_dia + 2, roller_thread_dia, l*4]);
+        }
     }
-    
-    %color("blue")
-    sphere(d = roller_dia, $fn = $fn);
 }
 
 module roller_mount() {
             roller_mount_tri_body();
         
             if (cut_roller_holder)
-            translate([0, -base_dia / 2 - 1, -40])
-            cube([base_dia / 2 + 1, base_dia + 2, 40]);
+            translate([0, -base_dia, -base_dia])
+            cube([base_dia *2 , base_dia * 2, base_dia*2]);
             
             
             for ( i = [0:len(sw)-1] ){