# mix volatiles and another gas (usually oxygen) to a target ratio, compensating for differences in temperature between the two inputs, and tweaking the ratio to correct for small deviations in the output mix (so it will get more accurate over time)

alias ingas1 d0
alias ingas2 d1
alias outgas1 d2
alias mixer d3
alias readout d4
alias h2frac d5

alias targeth2frac r15
alias mixerratio r14
alias molespertick r13
alias outreagents r12
alias outh2frac r11
alias pipe1h2frac r10
alias pipe2h2frac r9
alias pipe1temp r8
alias pipe2temp r9

define molespertick 26.144
define MAXOUT 400

start:
yield

s ingas1 On 1
s ingas2 On 1
s outgas1 On 1

move targeth2frac  0.5
bdns h2frac notarget
l targeth2frac h2frac Setting
notarget:

l outreagents outgas1 TotalMoles
l outh2frac outgas1 RatioVolatiles
select outh2frac outreagents outh2frac 0
l pipe1h2frac ingas1 RatioVolatiles
l pipe2h2frac ingas2 RatioVolatiles

l r0 outgas1 Pressure
bge r0 MAXOUT high

max r0 1 r0
mul r1 outreagents 101.325
div molespertick r1 r0
s db Setting molespertick

add r1 outreagents molespertick
mul r0 targeth2frac r1
mul r1 outreagents outh2frac
sub r0 r0 r1
mul r1 molespertick pipe2h2frac
sub r0 r0 r1

sub r1 pipe1h2frac pipe2h2frac
mul r1 r1 molespertick

div mixerratio r0 r1

# ^^
# (target*(moles+43.8)-moles*h2_frac - 43.8*p2_h2)/(43.8*(p1_h2-p2_h2))

l pipe1temp ingas1 Temperature
l pipe2temp ingas2 Temperature

mul r0 pipe1temp mixerratio
sub r1 1 mixerratio
mul r1 r1 pipe2temp
add r3 r0 r1
#r0 = mixerratio*temp1 + (1-mixerratio)*temp2

div r4 r0 r3

mul r2 r4 100
max r2 r2 0
min r2 r2 100

s mixer Setting r2

bdns readout over
l r0 outgas1 RatioVolatiles
mul r0 r0 100
s readout Setting r0
over:

j start

high:
s mixer On 0
j start