This should be relatively easy if you have the CD4029's already. One
of these chips can count from 0 to 9 provided you set the BINARY/
DECADE (pin-9) to a low level. Also put the UP/DOWN (pin-10) of this
part to a high level to enable counting in the upwards direction.
Counting to 99 will require two of the CD4029s. Connect the pin-9 and
pin-10 of both parts as discussed above. Also wire the PRESET input
(pin-2) on both parts to a low level. Wire the clocks in common to
both parts and connect to whatever it is that will advance the count.
On the first device (low digit counter) make sure to set the CARRY_IN
(pin-5) to a low level. Then take the CARRY_OUT (pin-7) of the first
counter and wire it to the CARRY_IN (pin-5) of the secound counter.
This latter connection allows the second high digit counter to step
only when the low digit counter is rolling over from nine back to
Since these are CMOS parts it is advisable to also tie all of the
JAM_LOAD (pins 3, 4, 12 and 13) inputs to low levels at both chips.
For the basic counter you desire no other chips should be required to
implement the 0-99 count sequence.
If you can't understand the incredibly simplified description in the
datasheet then your chances of even wiping your butt are next to nil.
Make yourself useful and volunteer to pick up litter in your
neighborhood or something.