I have only three things to say about Cygnal that I consider to be "factors" that you should know about in selecting the choice to use one of their parts.

These are:
1) The onboard flash is limited to what is on the part. There is no off chip code expansion. There are parts with up to 128K code FLASH bytes however and there are parts with external XRAM space expansion direct to 64K and banked to as large as you can imagine.

2) The parts with the I/O crossbar for I/O pin assignment do NOT allow any peripheral to any pin assignment. Note that on first blush it may seem like this is the intention of the cross bar...but it just does not work like a cross-point-switch...so read the data sheet carefully and make sure you have your I/O assignment figured out BEFORE you commit the pinout to the PCB layout.

3) The Cygnal parts are all 3.3V parts in surface mount packages that are not economically socketable. This can be a discouragement at first breath for some engineers but Cygnal does have very inexpensive evaluation boards that are very easy to prototype into a development system for almost any project as described here: http://www.8052.com/users/mkaras/CygnalEval.phtml .

Take these factors into consideration and then also appreciate the 1 and 2 clock instruction cycles, the full speed on-board FLASH, JTAG in system programming, JTAG in-system / on-chip full speed debugging, clocking rates up to 100 MHz, availability of peripheral selections that are awesome, on-board XRAM up to 8K bytes, and analogue capabilities with A/D, D/A and comparators; you will find a part family that is hard to turn away from!!

Michael Karas