Using a Microcontroller to replace TTL & CMOS ICs

[William At MyBlueRoom]

As many 74xx series TTL and 40xx CMOS ICs become harder to find and microcontrollers become more self contained and available.
It has generally been cheaper to use a microcontroller in complex TTL & CMOS designs but to replace one or two ICs seemed overkill.
PAL, GAL & PEEL were popular once and have evolved in to FPGAs

Well at $1 for some microcontrollers it's about the cost of some TTL / CMOS ICs I'm starting to use them in designs were I don't need the speed but I do need a custom function.

PS anyone here still use PALs or GALs? Can you even buy them anymore?

 

[Mike - K8LH]

I'm amazed when I realize a single PIC microcontroller and a handfull of 'glue' components can replace the Frequency Counter I built in the mid-70's using discrete 74LS90 counters, 74LS75 4-bit latches, and 74LS47 display drivers.

I remember several companies coming up with large single chip up/down counter solutions later which integrating those discrete functions (Maxim still makes some very nice 4-digit up/down counter chips).

All in all, I believe every electronic hobbyist/designer worth his/her weight in resistors (grin) should make an effort to learn about these incredible devices and their capabilities for custom low-component-count logic replacement.

Kind regards, Mike

 

[mramos1]

In 1980, I was using microprocessors (motorola and intel), and still needed TTL and CMOS chips. EEPROMS, RAM.

When I found the PIC (microcontrollers in general) I changed the way I did things on the spot. It is a custom chip for every occasion pretty much.. The flash on them and RAM built in. You can reprogram them, how can you beat it.. Everything in a single chip.

FPGA I sort of skipped over, but hear they are impressive, I have just not needed the speed or custom logic.

You do need a programmer for the microcontrollers (and FPGA), but a student/hobbyist can build one.

I agree with Mike, things have come a long way.

If the schools were up to date, they would teach microcontrollers. Maybe they are?

 

[William At MyBlueRoom]

FPGA I sort of skipped over, but hear they are impressive, I have just not needed the speed or custom logic.

I looked into GALs & PALs just before I got into PICs. I thought it was fun writing logic formulas... (not)