This is my first ( and very old now ) succesfull Jal&Pic application, here is the schematic:

I have made three identical panoply, ( named left, center and right) everyone have 6 groups of lights, three are yellow disposed in a rectangular shape, the other three are red, yellow and green disposed in a circular shape and one speaker who make noise with two different frequencies. In schematics it's figures only 6 leds, in reality every led is a group of n leds, of course this need some additional drivers. Because serial.jal library had special requirements which I don't understand at that moment, I had used Axel serial routine, you can download above schematics, JAL program ( serial.jal )and Axel library from here: serial.zip.For this left panoply, leds and speaker will be active sending ASCII caracters (taste 0 to 7 on PC keyboard) from a terminal emulator at 19200bps. Parameters of transmision must be set appropiate: 8 data bits, no parity, 1 stop bit and flow control can be either hardware or none. ICP socket means In Circuit Programming, this ICP it's strongly recomended to be added to any programmer and P1 is COM1.
 

Digital Clock

This clock use a modified Microchip AN615 schematics. I've tested  because PIC pins are used in an "aggressive mode", some of them are input and output in a sequence way. Watch the schematics:

For a good visibility of this multiplexed display, I have used 25 mm Kingbright seven segment display. Flickering is almost invisible with a refreshing rate of about  5mS . To keep functional the In Circuit Serial Programming capabilities, R1 must have a large value. All three setting buttons are connected in a smart way at the same pins who driving display segments. The program is doing a standard 24 hours format clock . To have better accuracy I've decided to change oscillator from 4.00MHz to 3.2768 MHz, so one second time base can be obtained without any software trick.  Here is the code, if you have some noticeable improvements please let me know. clock1.jal
Newest clock version ( 4,000 MHz quartz, interrupts, cucu ) it's in evaluating process now, but seems to be very accurate, with a correct compensation it lies me only +/- 5seconds/ month.
There is a simple methode to build ( using almost the same hardware and *only* a PIC ! ) a HH:MM:SS clock or a dual clock HH1:MM1 HH2:MM2 showing two different earth times. Do you know what I'm talking about ? If yes, your project can lie in the table below. If you are realy fascinated about time measuring, see my WEB PICx84 watch collection ( best regards to people who have built  these clocks, if zipped documentation was complete, including mail and web address, I could provide here a link to the owners page... )

Verdict	Source	Autor
Briliant:	mclock.zip	Bob Blick
Nice:	pictock.zip	John Becker
Interesting:	Jinx's clocks	Joe Colquitt
	first.zip	David Tait
	unclock.zip	Mike Predko
Common:	countdn.zip	Stan Ockers
	clkapic.zip	French design
	clock.zip	John Patterson
	binclk.zip	Peter Engles