have a look here:
http://www.matrixmultimedia.com/mmforum ... 12&p=14003
It was created when V4 was new to me, so its not the most advanced in the word, but it works well to alter led brightness, hence flash rate.
Also to learn more about flowcode 4 you can find a link to V4 examples here:
http://www.matrixmultimedia.com/Flowcode3a-X.php
Scroll down to flowcode extras, then you will see 'Flowcode V4 Examples'
What I do to learn is just load a flowcode example, then press F8, to run single step, then in variable windows, right click and select 'Add variable...'
If you want to add all variables then highlight top one, hold shift key, then left click on lowest variable, then click 'use variable'
You could either run simulation by holding down F8, or you can go to View, project options and change simulation speed from 'As fat as possible' to 1000. If left on 'As fast as possible' variables will not be displayed in variables window.
You could just read adc value, convert to a delay period. then a continuous loop of: led on, read ADC Calculate delay led on,delay, led off, delay
Also included a couple of very basic programs to get you started.
First one (LED Delay1) using reading 8 bit ADC
Second one (LED Delay2) using 10bit ADC and delay variable from 0 to 1023 ms . You don't have to stick with max 1023 ms Delay, using a formula you can go up to something like 32767 ms. Or Change delay form ms to Seconds.
Hope it helps.