CH was OK in it's day, but is out of date...
The documentation for the Flash version is copyrighted 2001. The Q&A page was last updated March of 2002. It doesn't support I2C, you have to roll your own. This is yet another good compiler left to go to seed.
I am impressed with how selection menus come up with access to all the available registers and gates inside the chip you selected to use. So, if the PIC you selected had one comparator, the comparator menus had initialization, set ups and functions for one comparator. If the PIC had two comparators, it had all of the previous possibilities, but for two comparators. The same goes for PWM, ADCs, etc. Everything you had to do, and could do, was in those menus. It was great for people adverse to read data sheets. There were other menus/lists that let you track variables used, and the list goes on.
To my mind the best feature of this compiler is the instant assembler code created on the spot as you entered a line of BASIC source. Just the thing for students.
I purchased the Flash 3.7 version in early 2004 for $97. They brought out ver.4 shortly after. They didn't support the 18F family as hoped. Instead they basically revamped the layout and icons. Big deal. Not worth the $upgrade.
At $188 for the Flash4, I can't recommend this for what you get, although it does have some neat features.
CH BASIC is the OTHER whiz-bang compiler I bought in 2003/2004 that showed real promise, then languished without meaningful upgrades. The first (Sept 2003) cost $230, so that was really painful, especially since I got it after they said the next major upgrade was due before Christmas. Three years later they are finally making all the right noises , but...
Check out Oshon Software at
https://oshonsoft.com/. He has two compilers, one for PIC16Fs, another for PIC18Fs. A bundle license for both these is 55 euros ($70.52 as of 11/16/06). These are the FULL compilers, not some halted version, and does many, many PICs. You can buy a license for one or the other for considerably less. This gets you the 32-bit math package and structured features packages for both. These two features can be purchased as separate from the compilers, for people that buy the REALLY LAME compiler(s) version(s) at lowest price.
If you want to add USB capabilities to the 18Fs that support it, you'll have to buy a separate license for 75 euros ($96.17 etc.).
All these prices given here are for the PERSONAL/HOBBYIST VERSIONS!! Commercial licenses are more.
There are two forums for these products, both weak on performance. You can find answers there, but the author is good about responding to questions, so the forums are almost unnecessary.
And, of course, there is MikroElectronica's BASIC. It too is quite capable. But, it is heavilly structured, not too friendly to beginners. The developers say as much, they had the semi-professional in mind. Their BASIC can be had for $99 as a download if you buy their development board (the EZPIC4, a perfectly GORGEOUS device, check it out!) for $145 (includes $25 for shipping). Look them up at
https://mikroe.com/.
Their forums are large and dynamic, with several knowlegable people lending their wisdom. And barbs.
For what it's worth,
kenjj