Any reason not to use a 16C54?

[William At MyBlueRoom]

I have a simple project in mind and although I'm a big fan of the 16F628A as it's cheap and a great chip;but I simply need a basic non reprogrammable micro. The 16C54 fits the bill. All the I/O I need for the project I have in mind and it's cheap too. $1.48 at mouser.

I'm amazed it's still be produced.

 

[Nigel Goodwin]

I have a simple project in mind and although I'm a big fan of the 16F628A as it's cheap and a great chip;but I simply need a basic non reprogrammable micro. The 16C54 fits the bill. All the I/O I need for the project I have in mind and it's cheap too. $1.48 at mouser.

Don't forget, you have to include the cost of the crystal for the C54, the F628 has an internal 4MHz oscillator - which probably makes it cheaper to use?.

As you're obviously aware, the C54 is a seriously old chip! - you also have the big expense of UV eraseable versions for development.

 

[William At MyBlueRoom]

Don't forget, you have to include the cost of the crystal for the C54, the F628 has an internal 4MHz oscillator - which probably makes it cheaper to use?.

As you're obviously aware, the C54 is a seriously old chip! - you also have the big expense of UV eraseable versions for development.

I'm seriously old
I have both the 16C54 & an ICE for it. Plus an UV eraser. I thought they killed it off, they did make it 40MHz though...

I've always used a crystal when using RS232 / RS485 communications anyways.

 

[Nigel Goodwin]

I've always used a crystal when using RS232 / RS485 communications anyways.

Why? - the internal 4MHz oscillator in the 628 is fine for 9600 baud, or even higher, but I usually only use 9600 anyway.

If you've got a big heap of 16C54's you may as well use them, but it's pretty pointless buying them now.

In fact I gave away a number of 16C57-XT's the other year, over 200 in tubes - I don't have a programmer for them, and I was given them, but couldn't bear to throw them away

In fact it was another moderator here who had them, we met at a radio rally at Elvaston Castle - quite funny as it turned out, we arranged to meet by the Russian Communications Truck - I was there, and he was at a different Russian truck

 

[Mike - K8LH]

I'm lookin' at the 16C54C Data Sheet and it looks like it's a 12-bit core with very limited resources compared to the '628A... Hardly worth the 30 cents savings if you were buying them...

Heck, if you've got a bunch of them on hand, you might as well use them...

BTW, I agree with Nigel... The 1% tolerance 4-MHz and 8-MHz INTOSC in many PICs provides very reliable serial communications as long as you avoid severe temperature extremes... And using special 1.8432, 3.6864, 7.3728, 9.2160, 11.0592, or 18.432-MHz "UART" crystals seems almost silly when you look at the bit rate errors for standard crystal frequencies -- even more so when using newer PICs with 16-bit SPBRG capability...

Have fun... Regards, Mike

**broken link removed**

 

[William At MyBlueRoom]

I'm lookin' at the 16C54C Data Sheet and it looks like it's a 12-bit core with very limited resources compared to the '628A... Hardly worth the 30 cents savings if you were buying them...

Heck, if you've got a bunch of them on hand, you might as well use them...

BTW, I agree with Nigel... The 1% tolerance 4-MHz and 8-MHz INTOSC in many PICs provides very reliable serial communications as long as you avoid severe temperature extremes... And using special 1.8432, 3.6864, 7.3728, 9.2160, 11.0592, or 18.432-MHz "UART" crystals seems almost silly when you look at the bit rate errors for standard crystal frequencies -- even more so when using newer PICs with 16-bit SPBRG capability...

Have fun... Regards, Mike

It will be in a pretty broad temperature range, outdoor, Canadian winter.

 

[motion]

If you're designing for a production run of less than a few thousand units, the cost savings is not worth the pain.

If you are designing for a run of tens of thousands of units, there are also pic16c54 clones out there.

The PIC16C54 is still available because there are existing applications developed in the last century that are still in continuous production.

 

[William At MyBlueRoom]

"pic16c54 clones" I thought there were none, the old senix was the only clone I knew of.

Well I took the advice of this thread, sniff I'll miss you little 16C54; but I'd miss a hardware USART, IRQs & Internal OSC more.

I've used a 16F628A in the attached schematic, the crystal will be optional (internal or resonator)
Now what to do with my favourite I/O pins (spare)

RB0 has an edge trigger IRQ
and
RA4 has an open collector output (great for iButton stuff)