Beyond TTL

[Henry]

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?

Thanks,
Henry

 

[Alexander]

"Henry" <henrytj@pghmail.com> schreef in bericht
news:LqqdnRyQTfFLX1neRVn-tQ@pghconnect.com...

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?

Thanks,
Henry


Try Microcontrollers or FPGA's

both are cheap to very expensive and easy to program with the right
software.
For some you must build a programmer or buy an "expensive" one.

For simpeler things you might consider GAL's or PAL's.

Alexander

 

[Derek Potter]

On Wed, 11 Jan 2006 03:41:38 -0500, "Henry" <henrytj@pghmail.com>
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.

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

Of course you could play about with some other logic families than TTL
but they all do much the same, just different voltage levels. CMOS is
sometimes useful in quasi-analogue applications as it has a huge input
resistance. the 40106 hex Schmitt inverter, for example can be used to
produce 6 independent oscillators. Also the 4051-3 are great for
switching analogue signals around - you can use them in audio
applications despite the fact they only cost a few pence as against
pounds for a "proper" audio switch. They are perfectly OK for all but
the most demanding hi-fi - where you might want 140dB s/n and .0001%
distortion for example.

As for interfacting to a PC, this can be a little tricky. I would
*not* recommend designing an internal PCI-bus card! The simplest
solution is to use a serial link. Miocrosoft, in their wisdom, are
calling RS232 "legacy" and have pressurized manufacturers to drop the
serial ports from PCs. However you can buy an inexpensive USB-serial
dongle whaich means you can then communicate from your PC over the USB
but driving it as a simple COM port. At the other end you can either
use a PIC/AVR with built-in serial ports or you can just drive some
digital lines directly, depending on which dongle you buy.

If you want to get more clever still, the same people (Future
Technology, in Scotland) provide similar devices to give you
Bluetooth. In both the Bluetooth and USB case, all the hard work of
implementing the network protocols is done for you. But interfacing to
a PC will take a bit of time whichever route you go. The simplest
approach is undoubtedly to get familiar with PIC processors using a
development board, then write your own serial drivers and construct
your own serial link separate from the one required for development.

Good luck.

 

[JeffM]

Are there programmable controllers on a chip
that are easy to work with.
...under $50 in parts
Henry

http://groups.google.com/group/comp.arch.embedded/browse_frm/thread/7840035dcb0249e3/7584f2f4877ea971?q=Atmel-AVR-controllers-best-for-teaching+straightforward-architecture+zzz+free-development-tools-including-gcc-compiler+jtag-debugger+gcc+sdcc+picp+no-good+no-real-good
http://groups.google.com/group/sci.electronics.basics/browse_frm/thread/32e180c24bba32c0/86a861146fcbc76b?q=AVR+*-C-compiler-is-free+*-GCC+*-*-*-PIC-*-*-programmed-in-assembler-*-because-the-assembler-is-free+*-don't-need-*-special-programmers+*-AVR-*-*-programmed-in-C+PIC-assembler-*-*-*-easy-to-learn+AVR-assembler-*-*-*-*-*-involved
http://groups.google.com/group/sci.electronics.design/browse_frm/thread/44ad1caf9218d30e/85bf1a1b9d9da3d7?q=looking-for-a-microprocessor-trainer+atmel-AVR-butterfly+added-for-USB+LCD+ADC+Com-port-programming+zzz+20-bucks+3v3-supply

 

[quietguy]

Henry, you will some very good stuff by doing a google search on 'picaxe'

PICAXES are microcontrollers that can be programmed in basic, the programming
software is free, and there is plenty of support on the net.

So, you can start playing for less than $10 - including the cost of a chip and
all the parts needed to allow programming from your computer

David

Henry wrote:

http://en.wikipedia.org/wiki/Microcontroller
"...For almost every bare microcontroller manufacturer, there are a dozen
little companies repacking them into a more hobbyist friendly package..."

So, can someone recommend a particularly good/inexpensive hobby/student
friendly manufacturer or supplier?

Thanks,
Henry