Hi Elec_mech.
I've now found on the internet a 10inch 7 segment digit, ordered it and wired it up to test. Works well. However not bright enough out doors. Only cost $9 (aus) a segment. Bargain - saves alot of stuffing around.
I've also since emailed asking for a brighter one and found one. I'll order one to test.
I've bought and tried a BCD switch for re-setting as you suggested - so much easier - fantastic.
I've also created a momentary "pause" as you suggested with a toggle switch to the clock (pin 15). I found it "flickered" so I grounded the connection with a 10k resistor (pull down resistor???). I just tried it and it worked. Is that the correct thing to do?
I've now got 4 small digits all wired up and counting down. However my next hurdles are:
1. When it reaches 00:00, it needs to stop. I'm planning on reading the binary output on the 4511's - maybe c=0 and d=0 on all digits - putting it through some sort of IC (nor, not, and - don't know yet - something) and making it "flip" the counter signal off. Is this correct?
2. My original "reset" was done so I could jump the "units" from 00 to 59 - not 99). Having added the 2 more digits, I've set those to preset to 44 (i.e. 44 minutes). So when I press the reset it goes to 44:59. However, I should stop the clock, press the reset and it should go to 45:00 instead. Then start the clock counting down. I've tried to add a second set of dip switches to also be able to set to 45:00 but to no avail. Any hints?
I've now found on the internet a 10inch 7 segment digit, ordered it and wired it up to test. Works well. However not bright enough out doors. Only cost $9 (aus) a segment. Bargain - saves alot of stuffing around.
I've also since emailed asking for a brighter one and found one. I'll order one to test.
I've bought and tried a BCD switch for re-setting as you suggested - so much easier - fantastic.
I've also created a momentary "pause" as you suggested with a toggle switch to the clock (pin 15). I found it "flickered" so I grounded the connection with a 10k resistor (pull down resistor???). I just tried it and it worked. Is that the correct thing to do?
I've now got 4 small digits all wired up and counting down. However my next hurdles are:
1. When it reaches 00:00, it needs to stop. I'm planning on reading the binary output on the 4511's - maybe c=0 and d=0 on all digits - putting it through some sort of IC (nor, not, and - don't know yet - something) and making it "flip" the counter signal off. Is this correct?
2. My original "reset" was done so I could jump the "units" from 00 to 59 - not 99). Having added the 2 more digits, I've set those to preset to 44 (i.e. 44 minutes). So when I press the reset it goes to 44:59. However, I should stop the clock, press the reset and it should go to 45:00 instead. Then start the clock counting down. I've tried to add a second set of dip switches to also be able to set to 45:00 but to no avail. Any hints?