The OTP devices I mean about C based chips Ex: The Historic 12C508A…..

Bathroom Extractor Fan Timer it’s a good product for the market too.

But the price different between C & Flash based ones becomes closer as earlier mentioned.

But I’m greedy about that Remaining FLASH Cycles LOL

Originally Posted by Gayan Soyza

You are going to make a Bathroom Extractor Fan Timer. After completing, the PIC must there permanent. So a FLASH based chip for that job would pointless. It can replace by an 8 pin OTP chip.

Due to very first time programming it must done with a FLASH based chip formatting over 100 of times to get the final output. After that can be converted to an OTP device. If you still don’t like then can replace the chip with a FLASH based one.

I see your point, yes flash is a waste of money if you're only going to program it once but I've decided to go for the PIC10F200-I/P as it's cheaper than the OTP unit from Maplins an at only six pins I won't have to drill many holes or do much soldering.

Looking at your requirement deeply

Pull the switch once – TURN ON output for 10 mins
Pull twice – TURN ON continuously
Pull again - TURN OFF

When it pulls ONCE within the 10 minutes time period what will happen? Does it continuous the timer or else?

When it pulls TWICE within the 10 minutes time period what it needs to do or do nothing?

For additional it will be good if you place 2 LED’s – one for 10 mins timer running & other for continuous running. Due to false input given by the user.

This small small things very useful when programming microcontrollers.

If the user pulls the cord once within half a second whilst the fan is off the timer will be activated.

If the user pulls the cord twice within half a second whilst the fan is of the continious mode will be operated.

If the user pulls the cord whilst the fan is on and the 0.5 second delay looking for a second pull has finished the fan is switched off.

Here's some heavilly simplified pseudo code:

Code:

Do
 Fan off
 If cord pull then
  Turn fan on
  If no cord pull within 0.5s then
   Set timer to 10min
  Else
   Set timer to 1day
  End if
  If cord pulled before time delay over then turn fan off
 End if
Loop

If you notice from my code, I've decided not to have a continious mode but to turn the fan on for a longer time period like a day, this is good as it means that if you go on holiday and forget to turn it off then it won't be on for too long. I might also make the on delay longer, it depends on how long it takes to clear a smell from the bathroom, I'll experiment with some cheap and nasty perfume.

By the way, this is probably a silly question but can this programer program other programmable chips like PLAs?

Also what about SMT PICs, is there an adaptor I can buy that I can attach the ZIF to program SMDs?

Originally Posted by Hero999

By the way, this is probably a silly question but can this programer program other programmable chips like PLAs?

I’m not familiar with PLA systems. But P16PRO40 supports to many chips including some 18F series. Unfortunately I couldn’t build this programmer because I don’t have a LPT port in my MB.I have some LVP programmers. See the supported devices in WINPIC site http://www.winpicprog.co.uk/supported.htm

Originally Posted by Hero999

Also what about SMT PICs, is there an adaptor I can buy that I can attach the ZIF to program SMDs?

There are some SMT to DIP adaptors as well. For more information see this link.
http://smt-adapter.com/Site/SMT-connector-adapters.htm

Originally Posted by eng

The PIC10F200-I/P is in a PDIP-8 package. Check the "Product Identification System" in the datasheet

What's the difference between a PDIP and a DIP?

Oh well I don't mind soldering eight holes although packaging a six pin device in an eight pin package seems a bit pointless to me.

Originally Posted by Gayan Soyza

I’m not familiar with PLA systems.

Programmable Logic Array (PLA) is a type of Programmable Logic Device (PLD), they were invented to replace 1000s of logic gates and flip-flops in logic circuits.

http://en.wikipedia.org/wiki/Programmable_logic_device

But P16PRO40 supports to many chips including some 18F series. Unfortunately I couldn’t build this programmer because I don’t have a LPT port in my MB.I have some LVP programmers. See the supported devices in WINPIC site http://www.winpicprog.co.uk/supported.htm[/url]

Parallel port cards are pretty cheap; you could probably get one for free from a trash PC.

There are some SMT to DIP adaptors as well. For more information see this link.
http://smt-adapter.com/Site/SMT-connector-adapters.htm

Wow they're expensive!

I take it that they're not solderless either?

I'm after something solderless, you just clip the part to the PCB, plug it into the ZIF socket and away you go!

Originally Posted by Hero999

What's the difference between a PDIP and a DIP?

No difference, PDIP = Plastic DIP
I was pointing out that the PIC10F200-I/P has eigth pins, if you're going to design the board. Instead, if you want the 6 pin version, you have to order the PIC10F200-I/OT, that comes in the SOT-23 package.

I wouldn't mind the SOT-23 package if there's a way I can adapt my ZIF socket to take it.

Originally Posted by Hero999

I wouldn't mind the SOT-23 package if there's a way I can adapt my ZIF socket to take it.

The best would be to use the ICSP connector on your programmer hooked to an ICSP connector on your target.

Or just solder the 3 ICSP wires to pads on the target board and insert the other end into the ZIF.
Maybe 2 more for power and GND. Take the wires off when the board is finished.

May be less painful to use the 8 pin DIP.

Originally Posted by 3v0

The best would be to use the ICSP connector on your programmer hooked to an ICSP connector on your target.

Or just solder the 3 ICSP wires to pads on the target board and insert the other end into the ZIF.
Maybe 2 more for power and GND. Take the wires off when the board is finished.

These are the best solutions IIRC the PIC10F200 has a 'strange' pin layout. In other words, even if he chooses the PDIP8 version, it can't be programmed in the socket. Another reason to prefer a PIC12Fxxx ?

So even if I by the eight pin package it can't be programmed in the socket?

That's pretty stupid.

Going back to what you said earlier:

Originally Posted by eng1

The PIC12C508A is an OTP device, not recommended.
The PIC12F508 looks good for your project, but it's not loaded with peripherals - that might become useful for future projects (ADCs, PWM) - and has a two levels stack. I would buy some PIC12F683s too (my personal favourite).

I forgot that RS sell the PIC12F508-I/SN £0.62 so, decision made, I'll go for it!

I'm not going to put the order in too quickly though (Corby is a bit of a drive); I'll wait untill there are quite a few things I need before I go.

not sure if this can help, but EasyPIC 4 development board have 2 different socket for 10F and 12Xxxx. They also sold that board... 12USD


http://www.mikroe.com/en/tools/experimental/pic/

LOL, thanks but no thanks - I've already built it!

Besides I prefer my project anyway as it has a ZIF socket, a built-in power supply and a nice case.

Perhaps I could build an adaptor for odd pinouts like the PIC10F200 as it would be cheaper than buying a new board but I'd rather avoid PICs like that altogether.

Bump.

Alright I'm putting an RS order now so I need to come to a final decision on what PICs to buy.

For the 8 pin DIP:
PIC12F508-I/SN
Order no: 623-0083
Price: 55p

For the 18 pin DIP:
PIC16F54-I/P
http://docs-europe.electrocomponents...6b80806d04.pdf
Order No: 623-0213
52p
Is this alright? I can't believe it's actually cheaper than the 8 pin DIP!
What's the catch?

All prices exclude VAT which is 17.5% in the UK.

I'll still get a few of the 12F508s anyway as it'll be worth 3p to save me drilling all those holes.

Originally Posted by Hero999

Bump.

Alright I'm putting an RS order now so I need to come to a final decision on what PICs to buy.

For the 8 pin DIP:
PIC12F508-I/SN
Order no: 623-0083
Price: 55p

For the 18 pin DIP:
PIC16F54-I/P
http://docs-europe.electrocomponents...6b80806d04.pdf
Order No: 623-0213
52p
Is this alright? I can't believe it's actually cheaper than the 8 pin DIP!
What's the catch?

All prices exclude VAT which is 17.5% in the UK.

I'll still get a few of the 12F508s anyway as it'll be worth 3p to save me drilling all those holes.

I have not read all through this thread but just wondered why you want to buy a 12f508 - these can only be programmed once. They were popular a few years ago because they were cheap - (often used for chipping playstations).

Sorry- it is the 12C508 i was thinking of that only can be programmed once.


Also the 16f54 is even more obsolete than the 16f84 - why don't you just get a 16f628?