On 2006-01-13, Derek Potter ll wrote:
On Wed, 11 Jan 2006 03:41:38 -0500, "Henry"
wrote:

Okay, now that I have dabbled and put some circuits together with some 25+
year old parts (7400 series TTL). What might I do if I were to be doing this
with newer, more up to date, technology? Are there programmable controllers
on a chip that are easy to work with. Keep in mind I am looking for things
that I can do with under $50 in parts, like with the TTL gates. Is there a
relatively easy way to interface simple logic gates/transistors with a PC,
laptop, PDA, etc?

It depends whether you are trying to teach yourself the hard way or
just get on with practical design. Gate arrays are one way to go but
are relatively inflexible and I would suggest you skip them and go
straight to microcontrollers. You'll need to learn programming skills
but the Microchip PIC series are fairly easy to learn, though you will
certainly spend a lot of time learning the ropes. It's worth it
though, so Google Microchip and get hold of their data CDs, download
their MPLAB software and (horror of horrors) *buy* a PICSTART
programmer. You can get FLASH chips that avoid the need for a UV
erasor, but the cheapest chips are the ones that come in a more
expensive UVEPROM version as well as the cheaper OTP (one time
programmable) types. It's your call what you use, the different types
have different built-in peripherals, you can always start with the
simplest (but avoid the PIC16C54 as it has a cumbersome page
addressing system).

As another poster has said, the AVR-core is the other "big name" in
microcontrollers. You can get some very fancy chips in that series.

the AVR are (hardware wise) way easier to program that the PICS
you don't need 12V (only a single supply somewhere near 5V ) and
they all have 1000-rewrite flash. a reliable in-circuit programmer
can be made using a single 74hc series chip....

You may like to budget for a development board in either case.

they're nice, but breadboard etc can be used too...

Bye.
Jasen