OK, OK, you guys have convinced me! I'll crack this nut with a sledge hammer, and finish it this year, if you'll help. Be gentle. It's my first Arduino. I've found the perfect solution -- the "Trinket." It's very small board (0.6" x 1.2") designed with headers so that it can be installed as a through-hole component. It has all the GPIO I need (5), and the cost is only $7.
In the schematic above, pressing S1 starts a 1-shot timer, turns on the LED, and outputs a short pulse on PB0. Unless S1 is pressed to abort the timer, at the end of the 1-shot period the timer is reset (or just stopped), the LED is turned off, and another short pulse is output from PB0. But if S1 is pressed during a 1-shot period, timing is terminated immediately, the LED turned off, and another short pulse is output on PB0.
The period of the 1-shot timer is stored in EEPROM in a variable having a decimal value of 1 to 8, which is the 1-shot period in units of 30 seconds. At startup this value is retrieved from EEPROM. A subroutine to be added later allows the 1-shot period to be customized by counting 1 to 8 presses of switch S2 when the timer is not active. This is referred to as "calibration" While a calibration is in progress, input from switch S1 is ignored. (As you can see, if the discrete component circuit is going to be replaced by a processor, let's make the most of the additional capability.)
The switches will be typical snap-action PCB switches, so inputs can be anything from a hundred milliseconds to several seconds, and debounce is probably necessary. I can live with whatever timing accuracy the internal clock gives us.
I've ordered a couple of Trinkets, and I have downloaded something called Arduino 1.8.4 (I thought I was downloading Arduino IDE). I get a warning that my Windows Firewall has blocked some features of Java. Can someone tell me what additional tools and/or software I will need to become as proficient as one of those primary school kids. I may try to lure one of those kids over with an ice cream cone to program this thing. Any help to get me setup will be appreciated. Once I get any kind of basic program that can be loaded with the boot loader, I can experiment with it by trial and error. Does the Arduino IDE include an editor that provides any help with syntax errors, etc?
okasional
I'm trying to design a device that uses a monostable 555 timer to provide an output signal of several minutes duration. The unique requirement is that if the timer receives only one start pulse it should run its full timing cycle, but if a second identical pulse is given (an abort pulse) while the timer is running, the 555 is reset immediately, and everything is back to the starting point.
