Digital Clock using LM8560

I got some doubts, I hope you'll clear my doubts.
CIRCUIT: https://www.electroniq.net/files/other/lm8560-digita-clock-negative.jpg

1) Why the Cycle1 and Cycle2 Resistor and AC transformer value not given? Is there any calculation to set the resistor values?
2) What is f = 900Hz?
3) Is this circuit possibility of working? 'cause have to buy the things.

First thing to do, is read the datasheet.

I think its big one to understand. I can't get. I'm a software student. But much interested in Electronics. I saw the last Circuit CLOCK APPLICATION CIRCUIT (Negative Power Supply) I think it's easy to build. What should I keep in mind.? or Can't I do without knowing the Data?

why all this, better make a clock with PIC micro. it works much better and you would learn something from that. see the microchip application note AN0652 and relevant source code using 16C54, and we can port it easily to 16F628A

TO: Sarma,
I'm a good programer. I can program any language just to know the syntax alone. I heard from my friend, PIC is need to program, it much hard and much cost to instal the program in the chip. From which tool we can program and install to the chip? What're the devices we need?

you can make a small programmer for F series chips at less than Rs150. PIC chips are sold almost any town like Kochi, Tiruvananthapuram etc, PIC16F628A just costs Rs 70/- or so in Indian currency. see the COM port based schematic designed by DL4YHF with external 15V power supply. it can wonderfully work for PIC16F728A.

microchip mplab and associated files are free for download. Hitech C is also with microchip and is free for limited usage with code lines limited. but you can always optimize.

i feel you get better satisfaction than using hardware based clocks that use mains frequency and the same is never 50HZ and with the power failures troubling the clock..

with micro, you can maintain the clock timing while display can be on when power is there and can be managed to show up under power failure from battery with a push switch, something like that to ensure power saving on battery.
just three cells make up 4.5 and the clock can happily work,