rogs
Well-known member
I have a guitarist friend who uses a looper pedal on stage to replay backing tracks.
Works well - but he hates having to press the looper control button twice , just to stop the device.
He approached a technically minded colleague, who told him that an interface to allow a single footswitch press, to both start and stop the unit, was "a simple task for an Arduino".
Problem was this 'simple' interface never materialised.... Always seemed to be stuck at the "just need to sketch a layout and write some simple code" stage....
I'm sure many of us know colleagues who often say that!
I thought this simple task was massive overkill for any kind of microcontroller - Arduino, PIC or otherwise - and told him I'd knock up an interface using simple CMOS logic.
(Some notes here of the project results : www.loop.jp137.com ). He uses the 'single switch' version and it works well.
Point is, I was quite surprised to find that many 4000 series CMOS logic ICs are still easily available and quite cheap - even from mainstream suppliers.
There even seem to be quite a lot of good old DIP 'thru-hole' variants still listed!
Why? --- I remember an old Phillips (NXP) data book published in around 1986 'recommending' that 4000 series 'should not be considered for new designs'..... And yet here we are, 35+ years on, with many of the devices still freely available.
Who's using them - they're certainly not being made just for 'stripboard hobbyists' like me.... There's only about 3 of us left
So, with the huge uptake in microcontrollers for control system designs, where are these old CMOS chips still being used in large enough quantities to justify ongoing active production - from major manufacturers like Texas for example?
Doesn't seem to make sense?.....
Works well - but he hates having to press the looper control button twice , just to stop the device.
He approached a technically minded colleague, who told him that an interface to allow a single footswitch press, to both start and stop the unit, was "a simple task for an Arduino".
Problem was this 'simple' interface never materialised.... Always seemed to be stuck at the "just need to sketch a layout and write some simple code" stage....
I'm sure many of us know colleagues who often say that!
I thought this simple task was massive overkill for any kind of microcontroller - Arduino, PIC or otherwise - and told him I'd knock up an interface using simple CMOS logic.
(Some notes here of the project results : www.loop.jp137.com ). He uses the 'single switch' version and it works well.
Point is, I was quite surprised to find that many 4000 series CMOS logic ICs are still easily available and quite cheap - even from mainstream suppliers.
There even seem to be quite a lot of good old DIP 'thru-hole' variants still listed!
Why? --- I remember an old Phillips (NXP) data book published in around 1986 'recommending' that 4000 series 'should not be considered for new designs'..... And yet here we are, 35+ years on, with many of the devices still freely available.
Who's using them - they're certainly not being made just for 'stripboard hobbyists' like me.... There's only about 3 of us left
So, with the huge uptake in microcontrollers for control system designs, where are these old CMOS chips still being used in large enough quantities to justify ongoing active production - from major manufacturers like Texas for example?
Doesn't seem to make sense?.....
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