here you see 2 do loop can work it may help you or not

                                    ` This code was downloaded from The Game Creators
                                    ` It is reproduced here with full permission
                                    ` http://www.thegamecreators.com
                                    
                                    REM Project:
REM Created: 10/11/2006 01:30:52

` here you see 2 do loop can work
` it may help you or not

` set up the sync rate
sync on: sync rate 30
 `goto point
top:

`start the main loops
do
`clear the screen
cls
`make a value so you can swich loops
a=a+1
`display value
print a

if a=100
exit
endif

`end the loop
sync
loop

`let the program run into the next loop
do
`clear the screen
cls
`display value
print a
`change the value to count dawn
a=a-1
`set up a way to swith  back to the frist loop
if a =0
goto top:
endif
`end the loops
sync
loop
` end the program
end