Beginner, need help interpreting notation


Hello, I'm completely new to maxscripts, I found a script to use for my purpose and it has been working fine but it's coming to a time where I need to learn the finer points of what the hex numbers mean in a vertex buffer. I opened up the script and I think I've found information that could help me better understand the subject matter however I am having problems understanding the script notation. The relevant script extract is as follows and appears to describe the vertex buffer.

for v = 1 to num_verts do (
fseek l pos #seek_set
vx=0; vy=0; vz=0; nx=0; ny=0; nz=0
tu1=0; tv1=0; tu2=0; tv2=0
tu3=0; tv3=0; tu4=0; tv4=0
b1=1; b2=0; b3=0; b4=0
w1=1.0; w2=0.0; w3=0.0; w4=0.0
for c = 1 to fvf_table.count do (
fseek l (pos+fvf_table[c].position) #seek_set
val = readvertex fvf_table[c].type l
case fvf_table[c].component of (
#POSITION: (vx=val[1];vy=val[2];vz=val[3])
#NORMAL: (nx=val[1];ny=val[2];nz=val[3])
#BLENDWEIGHT: (w1=val[4];w2=val[3];w3=val[2];w4=val[1])
if b1==b4 do b4=0
if b1==b3 do b3=0
if b1==b2 do b2=0
if b2==b4 do b4=0
if b2==b3 do b3=0
if b3==b4 do b4=0
case fvf_table[c].layer of (
1: (tu1=val[1];tv1=val[2])
2: (tu2=val[1];tv2=val[2])
3: (tu3=val[1];tv3=val[2])
4: (tu4=val[1];tv4=val[2])

append vertArray ([vx,-vz,vy]*model_scale)
append normArray [nx,-nz,ny]
append uvwArray1 [tu1,(1-tv1),0]
append uvwArray2 [tu2,(1-tv2),0]
append uvwArray3 [tu3,(1-tv3),0]
append uvwArray4 [tu4,(1-tv4),0]
append weightArray [w1,w2,w3,w4]
append boneidArray [b1,b2,b3,b4]

-- errvert = 140
-- if vertArray.count == errvert do (
-- format "Object % \n" obj
-- print boneidArray[errvert]
-- printblockpos ("Bad Weight "+(v as string)) pos
-- format "Stride: %\n" stride
-- print fvf_table
-- )

from this I'm understanding that for 1 vertical of
3A 90 98 FB BC CC F7 78 3D 95 76 0F 4A FB F4 CE 00 00 F3 0C 00 00 01 08 59 C0 15 2D 3A 27 2F 9F 39 F9 3A 84 3A 27 2F 9F 3A 27 2F 9F

first is 3 floats of x, z, y but I can't understand how the 3A 90 98 FB value (which appears to be world co ordinate of x) is derived. The script seems to say vx=nx=w4 but i'm just not seeing it. Am I reading the notation wrong?

any help would be greatly appreciated.