constant Billion 1000000000
constant Million 1000000
constant Thousand 1000
constant HalfMillion 500000
constant SizeOfInt 4
constant MillionX10 10000000

//
// Add 2 x 18 digit integers, return result in p
// m, n, p are the base addresses of integer arrays
// p()=m()+n()
//
function AddMN2P(m,n,p)
dim i,Cy

i=peek(m) + peek(n)
Cy=i / Billion
i=i % Billion
poke(p+0,i)

i=peek(m+SizeOfInt) + peek(n+SizeOfInt) + Cy
i=i % Billion
poke(p+SizeOfInt,i)

endf

//
// Add 2 x 18 digit integers, return result in m
// m, n are the base addresses of integer arrays
// m()=m()+n()
//
function AddMN2M(m,n)
dim i,Cy

i=peek(m) + peek(n)
Cy=i / Billion
i=i % Billion
poke(m,i)

i=peek(m+SizeOfInt) + peek(n+SizeOfInt) + Cy
//Cy=i / Billion
i=i % Billion
poke(m+SizeOfInt,i)

endf


//
// Sub 2 x 18 digit integers, return result in p
// m, n, p are the base addresses of integer arrays
// p()=m()-n()
//
function SubMN2P(m,n,p)
dim i,Cy

i=peek(m) - peek(n) + Billion
Cy=1 - i / Billion
i=i % Billion
poke(p+0,i)

i=peek(m+SizeOfInt) - peek(n+SizeOfInt) - Cy +Billion
//Cy=i / Billion
i=i % Billion
poke(p+SizeOfInt,i)

endf


//
// Sub 2 x 18 digit integers, return result in m
// m, n are the base addresses of integer arrays
// m()=m()-n()
//
function SubMN2M(m,n)
dim i,Cy

i=peek(m) - peek(n) + Billion
Cy=1 - i / Billion
i=i % Billion
poke(m,i)

i=peek(m+SizeOfInt) - peek(n+SizeOfInt) - Cy + Billion
//Cy=i / Billion
i=i % Billion
poke(m+SizeOfInt,i)

endf

//
//m, p are the addresses of the first element of the arrays
//p()=m() / 1,000,000
//
function Div1e6M2P(m,p)
dim i,j,Cy,n
dim r$[32]

//m(0)
i=peek(m)
//print "A, i=";print format$( "%9u", i );print "\n"

//m(1)
j=peek(m+SizeOfInt)
//print "A, j=";print format$( "%9u", j );print "\n"

//Add 500000 to make sure we round correctly
i=i+HalfMillion

//Any Carry
Cy=i/Billion

if Cy
i=i % Billion
j=j+Cy
endif

//Now throw away the bottom six digits
i=i / Million
//print "B, i/Million=";print format$( "%9u", i );print "\n"

Cy=j % Million
//print "A, Cy=";print format$( "%9u", Cy );print "\n"

j=j / Million
//print "B, j/Million=";print format$( "%9u", j );print "\n"

//9 Digits per integer var so we divided by 1E6 so the remainder
//has to be multiplied by 1E3
i=i+(Cy*Thousand)
//print "C, i+Cy*Thousand=";print format$( "%9u", i );print "\n"

//Return the results
poke(p+0,i)
poke(p+SizeOfInt,j)

endf


//
// Return String representation of 18 digit BCD variable
//
function BCD2Asc$(m)
return format$( "%9u", peek(m+SizeOfInt) ) + format$( "%9u", peek(m) )
endf


//
// This is a test harness for testing ByPic's capabilities to calculate
// the 32 bit tuning word for an AD9850 DDS chip. The assumptions are that
// the AD9850 is clocked at 125,000,000 Hz, ie as commonly found on eBay
// for the cheap modules.
//
function start()
dim I(2),J(2),K(2),L(2),R$[24]
dim n,i

//10MHz Tuning Word for an AD9850 with CLK=125MHz scaled by 1e6
I(0)=383680000
I(1)=343597
print "Starting I()=";print BCD2Asc$(?I(0));print "\n"

//Increment to add/subtract to the tuning word for a 10,000Hz shift in frequency
J(0)=597383680
J(1)=343
print "Starting J()=";print BCD2Asc$(?J(0));print "\n"

//Move frequency up 10 KHz
//Result should be 343940981063680
tmr_set(?TIMER23, MillionX10)
for i=1 to 100
//AddMN2P(?I(0),?J(0),?I(0))
AddMN2M(?I(0),?J(0))
next i
n=tmr_get(?TIMER23);tmr_set(?TIMER23, 0)
print n/100 ;print " uS AddMN2M";print ""
print BCD2Asc$(?I(0));print "\n"

//Move frequency down 10 KHz
//Result should be 343253786296320
tmr_set(?TIMER23, MillionX10)
for i=1 to 100
//SubMN2P(?I(0),?J(0),?I(0))
SubMN2M(?I(0),?J(0))
next i
n=tmr_get(?TIMER23);tmr_set(?TIMER23, 0)
print n/100 ;print " uS SubMN2M";print ""
print BCD2Asc$(?I(0));print "\n"

//Divide RawTuning Word by 1E6 to get actual tuning word we will send
//to the DDS chip
//Result should be 347033358
tmr_set(?TIMER23, MillionX10)
for i=1 to 100
Div1e6M2P(?I(0),?L(0))
next i
n=tmr_get(?TIMER23);tmr_set(?TIMER23, 0)
print n/100 ;print " uS Div1E6";print ""
print BCD2Asc$(?L(0));print "\n"

print "Tuning Word is ";print toupper$(hex$(L(0)));print "\n"

endf