Fred said:
No- BCD and BINARY are the same for digits 0->9, no translation
required. The schematic is intended to show that P0,P1,P2,P3 are
connected to GND on the units counter- the horizontal line just below
the join point indicates COMMON or GND. On the TENS counter, P1 and P3
connect to GND, and P0 and P2 connect to the output of UB 74HCT10. Also
check to see that UB output goes low at count of 9 and is connecting to
/SPE, the parallel load input of the counter. Double check the
interconnections- you will find something simple.
It will work most of the time but there is a possibility of a glitch
count that will really throw everything off. The series capacitor and
diode make this impossible.
I have enclosed a new schematic that should clear up the problems. The
"10 HOUR TIMER" portion has also been changed- the CI input on the
SECONDS counters cannot be tied to VCC as originally shown- it must be
joined to the PEC line from the FREEZE CTL as shown- now you can tie
each individual counter PE to VCC locally at each chip. This make the
counters freeze if you happen to catch them in the rollover count
stage-59 etc.
Please view in a fixed-width font such as Courier.
BASIC DIVIDE BY 60 COUNTER W/BCD OUTPUT
(BDB60CW/BO)
SCHEMATIC
UNITS TENS
TO DISPLAY TO DISPLAY
/------^------\ /------^------\
| | | | | | | |
| | | | | | | |
+-------------------------+ +--------------------------+
| | | | | | | | | | | |
| | | | | _ UB | | | | | | _ UE |
| | | | +-----| \ | | | | +--|-----| \ |
+--|----|--|--|--|-----| O--+ | | | | | | O--+
| | +--|--|--|-----|_/ | | +--|--|--|-----|_/ |
| | | | | | 'HCT10| | | | | | 'HCT00|
| | +--------------UA | | +--------------UD |
| | | Q0 Q1 Q2 Q3 | | | | Q0 Q1 Q2 Q3 | |
| | | --- | | | | --- | |
| +-| SPE | | +--| SPE | |
| | | | | | |
| | -- | | ___ UC | -- | |
| | MR |-+ +-\ \ | MR |-+ |
CI>+----| TE | | | | O---| TE | | |
| | | +-/__/ | | | |
+-|>CLK | | | 'HCT02 | 74HCT163 | | |
| | 74HCT163 | | +--|---------|>CLK | | |
| | | | | | | | | |
PEC>+---| PE | | | | +-----| PE | | |
| | | | | | | | | | | |
| | | P0 P1 P2 P3 | | | | | | P0 P1 P2 P3 | | |
| | +---------------+ | | | | +---------------+ | |
| | | | | | | | | | | | | | | |
| | +--+--+--+ | | | | | +-----+-+ | |
| | | | | | | | | | | |
| | --- | | | | +---+-----+ --- | |
| | com | | | | | com | |
+-|-------------------|--|--|---+ | +-----------------+
| | | | | | |
| | | | | | __ UF |
CCLK>-+----------------------+ +---------+--------\ \ |
| | | O-------> CO
| +--/__/ |
| 'HCT02 |
__ | |
MR>-----------------------+---------------------------------+
SYMBOL
BDB60CW/BO
+-----------+ 4
----|PEC UNITS|--/--> | | 4
----|CI TENS|--/--> | |
----|>CCLK | |__ CO|----->
----|MR |
+-----------+
FREEZE CONTROL SCHEMATIC SYMBOL
+------+
| |PEC
0.1u |FREEZE|->
com---||--+ | CTL |
| +------+
100K | 10K
+--/\/\--+---/\/\--+ 'HCT00
| 10K | __
5V >-+--/\/\-----------------+--------------| \
| 100K | | | o-+-->PEC
+--/\/\-+ | | +--|__/ |
| | | | |
| | o run +-|--------+
1Hz | 1000p | | |
CLK >---|<|---+---||--------o SW | +--------+
1N4148 | | \ | |
=== | o freeze | 'HCT00 |
10p | | | __ |
| | | +----| \ |
--- | | | o-+
com +----+--------------|__/
10 HOUR DISPLAY TIMER
+------+
| |PEC
|FREEZE|->>---------------------+
| CTL | |
+------+ +-----+---------------|--+----------VCC
| | | |
\ | | |
1K +---------------+ | |
\ | | | | | S
START / | | +-------------------+ 4 E
_ | | | | -- C C P UNITS|--/--> C
+--o o---+--|--|------| MR C I E | 4 O
| NC | | | | L C TENS|--/--> N
--- | | | | K | D
| | | | CO | S
| | | +-----------BDB60CW/BO
| | | |
| | +---------------|--+
| | | | |
| | | | |
| | | | |
1Hz CLK-------+---------------+ | |
| | | | | | M
| | | +-------------------+ 4 I
| | | | -- C C P UNITS|--/--> N
+------------| MR C I E | 4 U
| | | | L C TENS|--/--> T
| | | | K | E
| | | | CO | S
| | | +--------+--BDB60CW/BO
| | | |
| | +------------------+
| | | |
| +---------------+ | |
| | | |
| | | | H
| +-------------------+ 4 O
| | -- C C P UNITS|--/--> U
+------------| MR C I E | R
| L C TENS|N/C S
| K |
| CO |
+-----------BDB60CW/BOM
N/C
HOURS
TO DISPLAY
/------^------\
| | | |
| | | |
+-------------------------+
| | | | | |
| | | | | _ UB |
| | | | +-----| \ |
+--|----|--|--|--|-----| O--+
| | +--|--|--|-----|_/
| | | | | | 'HCT10
| | +--------------UA
| | | Q0 Q1 Q2 Q3 |
| | | --- |
| +-| SPE |
| | |
| | -- |
| | MR |-+
CI>+----| TE | |
| | |
CCLK>----|>CLK | |
| 74HCT163 | |
| | |
PEC>----| PE | |
| | |
| P0 P1 P2 P3 | |
+---------------+ |
| | | | |
+--+--+--+ |
| |
--- |
__ com |
MR>-----------------------+