10hr Timer Design Help

B

BM

Guest
Can anyone help point me in the right direction?

I want to make a timer circuit using discreet components (i.e. no pics or
stamps or inputs from a PC) that will count from 0 when it turns on up to
9hrs 59mins 59secs. I also want to display the hrs, mins and secs via
7-segment displays. In addition, I would like to be able to freeze and
display the clocks count at any given moment via a hold button.



thanks
 
Well, by discrete components, are you saying "no integrated circuits"?
If you go for a microcircuitry solution, this is trivial and a bit of busy
work if you use gates and counters. Not hard, mind you, but detailed. If you
go for a digital counter/multiplexor chip, many function as timer or counter
devices in HH:MM:SS format.
If you truly mean discrete components only, be prepared to make a big box
full of transistors and diodes as you will have to build your own gates and then
make counters and decoders and drivers. This would be a really complex task and
cost a lot.

Cheers!

Chip Shults
My robotics, space and CGI web page - http://home.cfl.rr.com/aichip
 
Why are you intentionally making your life difficult? You want to
replace one chip and a couple of hours learning with a couple of
handfuls of chips, days of debugging, and a damn sight more to learn
than with a micro? A wholly pointless excercise unless the objective is
to learn how to design logic circuits.

Al

BM wrote:
Can anyone help point me in the right direction?

I want to make a timer circuit using discreet components (i.e. no pics or
stamps or inputs from a PC) that will count from 0 when it turns on up to
9hrs 59mins 59secs. I also want to display the hrs, mins and secs via
7-segment displays. In addition, I would like to be able to freeze and
display the clocks count at any given moment via a hold button.



thanks
Click to expand...
 
BM wrote:
Can anyone help point me in the right direction?

I want to make a timer circuit using discreet components (i.e. no pics or
stamps or inputs from a PC) that will count from 0 when it turns on up to
9hrs 59mins 59secs. I also want to display the hrs, mins and secs via
7-segment displays. In addition, I would like to be able to freeze and
display the clocks count at any given moment via a hold button.
Click to expand...
It will look something like this:

The FREEZE may need synchronization- you don't say whether you want just
the display to freeze while count continues or the count should freeze
also. The 1Hz timebase can be derived any number of ways like an
external oscillator or divided mains frequency etc.

Please view in a fixed-width font such as Courier.


BASIC DIVIDE BY 59 COUNTER W/BCD OUTPUT

(BDB59CW/BO)


SCHEMATIC
UNITS TENS
TO DISPLAY TO DISPLAY
/------^------\ /------^------\
| | | | _ UB | | | | _ UE
| | | +-----| \ | | +--|-----| \
| | | | | O--+ | | | | | O--+
VCC +--|--|--|-----|_/ | VCC +--|--|--|-----|_/ |
| | | | | UA 'HCT00| | | | | | UD 'HCT00|
| +---------------+ | | +---------------+ |
| | Q0 Q1 Q2 Q3 | | | | Q0 Q1 Q2 Q3 | |
| | --- | | | | --- | |
+--| SPE | | +--| SPE | |
| | | | | |
| -- | 10K | ___ UC | -- | 10K |
| MR |-+/\/\-+-\ \ | MR |-+/\/\-+
CI>-----| TE | | | | O---| TE | | |
| | | +-/__/ | | | |
+-|>CLK | | | 'HCT02 | 74HCT163 | | |
| | 74HCT163 | | +--|---------|>CLK | | |
| | | | | | | | | |
PEC>+---| PE | | | | +------| PE | | |
| | | | | | | | | | | |
| | | P0 P1 P2 P3 | | | | | | P0 P1 P2 P3 | | |
| | +---------------+ | | | | +---------------+ | |
| | | | | | | | | | | | | | | |
| | +--+--+--+ | | | | +--+--+--+ | |
| | | | | | | | | |
| | --- | | | | --- | |
| | | | | | +--------------------------+
+-|-------------------|--|--|--+ | ___ UF |
| | | | +-\ \ |
| | | | | O-----------------> CO
CCLK>-+----------------------+ +--------/__/ |
__ | 'HCT02 |
MR>-----------------------+---------------------------------+


SYMBOL


BDB59CW/BO
+-----------+ 4
----|PEC UNITS|--/--
| | 4
----|CI TENS|--/--
| |
----|>CCLK |
|__ CO|-----
----|MR |
+-----------+
Click to expand...







10 HOUR DISPLAY TIMER

FREEZE
-+- 10K
+--o o---------+------------------+---/\/\-+-VCC
| | | |
--- +---------------+ +--|--------+
| | | | | 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
| | | +-----------BDB59CW/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
| | | | +--------+--BDB59CW/BO
| | | | |
| | | | | 'HCT00
| | | +------------|-------| \
| | | | | O--|
| | | +-------|_/ |
| | | |
| | +------------------+ 'HCT02|
| | | / /---+
| +---------------+ +--|---o | |
| | | | \_\---+
| | | | H
| +-------------------+ 4 O
| | -- C C P UNITS|--/--> U
+------------| MR C I E | R
| L C TENS|N/C S
| K |
| CO |
+-----------BDB59CW/BO
N/C

OMIT UC, UD, UE, UF
 
Fred Bloggs wrote:

Please view in a fixed-width font such as Courier.


BASIC DIVIDE BY 59 COUNTER W/BCD OUTPUT

(BDB59CW/BO)


SCHEMATIC
UNITS TENS
TO DISPLAY TO DISPLAY
/------^------\ /------^------\
| | | | _ UB | | | | _ UE
| | | +-----| \ | | +--|-----| \
| | | | | O--+ | | | | | O--+
VCC +--|--|--|-----|_/ | VCC +--|--|--|-----|_/ |
| | | | | UA 'HCT00| | | | | | UD 'HCT00|
| +---------------+ | | +---------------+ |
| | Q0 Q1 Q2 Q3 | | | | Q0 Q1 Q2 Q3 | |
| | --- | | | | --- | |
+--| SPE | | +--| SPE | |
| | | | | |
| -- | 10K | ___ UC | -- | 10K |
| MR |-+/\/\-+-\ \ | MR |-+/\/\-+
CI>-----| TE | | | | O---| TE | | |
| | | +-/__/ | | | |
+-|>CLK | | | 'HCT02 | 74HCT163 | | |
| | 74HCT163 | | +--|---------|>CLK | | |
| | | | | | | | | |
PEC>+---| PE | | | | +------| PE | | |
| | | | | | | | | | | |
| | | P0 P1 P2 P3 | | | | | | P0 P1 P2 P3 | | |
| | +---------------+ | | | | +---------------+ | |
| | | | | | | | | | | | | | | |
| | +--+--+--+ | | | | +--+--+--+ | |
| | | | | | | | | |
| | --- | | | | --- | |
| | | | | | +--------------------------+
+-|-------------------|--|--|--+ | ___ UF |
| | | | +-\ \ |
| | | | | O-----------------> CO
CCLK>-+----------------------+ +--------/__/ |
__ | 'HCT02 |
MR>-----------------------+---------------------------------+
Click to expand...
Add diodes to schematic like so:

Please view in a fixed-width font such as Courier.






BASIC DIVIDE BY 59 COUNTER W/BCD OUTPUT

(BDB59CW/BO)


SCHEMATIC
UNITS TENS
TO DISPLAY TO DISPLAY
/------^------\ /------^------\
| | | | _ UB | | | | _ UE
| | | +-----| \ | | +--|-----| \
| | | | | O--+ | | | | | O--+
VCC +--|--|--|-----|_/ | VCC +--|--|--|-----|_/ |
| | | | | UA 'HCT00| | | | | | UD 'HCT00|
| +---------------+ | | +---------------+ |
| | Q0 Q1 Q2 Q3 | | | | Q0 Q1 Q2 Q3 | |
| | --- | | | | --- | |
+--| SPE | | +--| SPE | |
| | | | | |
| -- | 10K | ___ UC | -- | 10K |
| MR |-+/\/\-+-\ \ | MR |-+/\/\-+
CI>-----| TE | | | | O---| TE | | |
| | | +-/__/ | | | |
+-|>CLK | | | 'HCT02 | 74HCT163 | | |
| | 74HCT163 | | +--|---------|>CLK | | |
| | | | | | | | | |
PEC>+---| PE | | | | +------| PE | | |
| | | | | | | | | | | |
| | | P0 P1 P2 P3 | | | | | | P0 P1 P2 P3 | | |
| | +---------------+ | | | | +---------------+ | |
| | | | | | | | | | | | | | | |
| | +--+--+--+ | | | | +--+--+--+ | |
| | | | | | | | | |
| | --- | | | | --- | |
| | | | | | +--------------------------+
+-|-------------------|--|--|--+ | ___ UF |
| | | | +-\ \ |
| | | | | O-----------------> CO
CCLK>-+----------------------+ +--------/__/ |
__ | 'HCT02 |
+--|<|-+ |
| 1N4148 |
MR>----------------+------------------------|<|-------------+
1N4148
 
BM wrote:

Can anyone help point me in the right direction?

I want to make a timer circuit using discreet components (i.e. no pics or
stamps or inputs from a PC) that will count from 0 when it turns on up to
9hrs 59mins 59secs. I also want to display the hrs, mins and secs via
7-segment displays. In addition, I would like to be able to freeze and
display the clocks count at any given moment via a hold button.
Click to expand...
Sounds like a school project to me.

Blake
--
Drop 'pants' to reply by email
 
Parts count works out better with this:

Please view in a fixed-width font such as Courier.


BASIC DIVIDE BY 59 COUNTER W/BCD OUTPUT

(BDB59CW/BO)


SCHEMATIC
UNITS TENS
TO DISPLAY TO DISPLAY
/------^------\ /------^------\
| | | | _ UB | | | | _ UE
| | | +-------| \ | | +--|-----| \
| | | | | O--+ | | | | | O----+
VCC +--|--|--|-------|_/ | VCC +--|--|--|-----|_/ |
| | | | | 'HCT00| | | | | | 'HCT00 |
| +--------------UA | | +--------------UD |
| | Q0 Q1 Q2 Q3 | | | | Q0 Q1 Q2 Q3 | |
| | --- | | | | --- | |
+--| SPE | | +--| SPE | UG |
| | UF | | | 'HCT08 |
| | 'HCT08 | ___ UC | -- | / |---+
| -- | / |---+-\ \ | MR |-| | |
CI>-----| TE MR |-| | | | O---| TE | \__+-+ |
| | \__+-+ +-/__/ | | +-----+ |
+-|>CLK | +---+ | 'HCT02 | 74HCT163 | | |
| | 74HCT163 | | | | | |
| | | | +--|---------|>CLK | | |
PEC>+---| PE | | | | +------| PE | | |
| | | | | | | | | | | |
| | | P0 P1 P2 P3 | | | | | | P0 P1 P2 P3 | | |
| | +---------------+ | | | | +---------------+ | |
| | | | | | | | | | | | | | | |
| | +--+--+--+ | | | | +--+--+--+ | |
| | | | | | | | | |
| | --- | | | | --- | |
| | | | | | +----------------------------+
+-|---------------------|--|--|--+ | ___ UF |
| | | | +-\ \ |
+-+ | | | | O-----------------> CO
CCLK>-+----------------------+ +--------/__/ |
| 'HCT02 |
| |
__ | |
MR>-----------------------+---------------------------------+

SYMBOL

BDB59CW/BO
+-----------+ 4
----|PEC UNITS|--/--
| | 4
----|CI TENS|--/--
| |
----|>CCLK |
|__ CO|-----
----|MR |
+-----------+
Click to expand...






10 HOUR DISPLAY TIMER

FREEZE +---------------------------------+
-+- | 1K |
+--o o---------+------------------+---/\/\-+-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
| | | +-----------BDB59CW/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
| | | | +--------+--BDB59CW/BO
| | | | |
| | | | | 'HCT00
| | | +------------|-------| \
| | | | | O--+
| | | +-------|_/ |
| | | |
| | +------------------+ 'HCT00|
| | | / |---+
| +---------------+ +--|---o | |
| | | | \_|---+
| | | | H
| +-------------------+ 4 O
| | -- C C P UNITS|--/--> U
+------------| MR C I E | R
| L C TENS|N/C S
| K |
| CO |
+-----------BDB59CW/BOH
N/C

Make HOURS counter like so:


HOURS
TO DISPLAY
/------^------\
| | | | _ UB
| | | +-------| \
| | | | | O--+
VCC +--|--|--|-------|_/ |
| | | | | 'HCT00|
| +--------------UA |
| | Q0 Q1 Q2 Q3 | |
| | --- | |
+--| SPE | |
| | |
| -- | 10K |
| MR |---+/\/\-+
CI>-----| TE | |
| | |
+-|>CLK | |
| | 74HCT163 | |
| | | |
PEC>----| PE | |
| | | |
| | P0 P1 P2 P3 | |
| +---------------+ |
| | | | | |
| +--+--+--+ |
| | |
| --- |
| |
| |
| |
CCLK>-+ |
|
__ 1N4148 |
MR>---------|<|-----------+
 
BM wrote:
Can anyone help point me in the right direction?

I want to make a timer circuit using discreet components (i.e. no pics or
stamps or inputs from a PC) that will count from 0 when it turns on up to
9hrs 59mins 59secs. I also want to display the hrs, mins and secs via
7-segment displays. In addition, I would like to be able to freeze and
display the clocks count at any given moment via a hold button.



thanks
Click to expand...
The circuit below is the most economical in terms of gates required- not
to mention the count logic is correct:

IC notation is for 74HCT163 at http://www.ti.com

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 | |
+-|-------------------|--|--|---+ | +-----------------+
| | | | | | |
| | | | | | __ UF |
CCLK>-+----------------------+ +---------+--------\ \ |
| | | O-------> CO
| +--/__/ |
| 'HCT02 |
__ | |
MR>-----------------------+---------------------------------+



SYMBOL

BDB60CW/BO
+-----------+ 4
----|PEC UNITS|--/--
| | 4
----|CI TENS|--/--
| |
----|>CCLK |
|__ CO|-----
----|MR |
+-----------+
Click to expand...





10 HOUR DISPLAY TIMER

FREEZE +---------------------------------+
-+- | 1K |
+--o o---------+------------------+---/\/\-+-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 | |
+---------------+ |
| | | | |
+--+--+--+ |
| |
--- |
__ |
MR>-----------------------+
 
This one adds an asynchronous FREEZE control using the remaining 2x
NANDS- action takes effect on inactive negative going clock edge so that
it is glitch proof:

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 | |
+-|-------------------|--|--|---+ | +-----------------+
| | | | | | |
| | | | | | __ UF |
CCLK>-+----------------------+ +---------+--------\ \ |
| | | O-------> CO
| +--/__/ |
| 'HCT02 |
__ | |
MR>-----------------------+---------------------------------+



SYMBOL

BDB60CW/BO
+-----------+ 4
----|PEC UNITS|--/--
| | 4
----|CI TENS|--/--
| |
----|>CCLK |
|__ CO|-----
----|MR |
+-----------+
Click to expand...




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 | |
+---------------+ |
| | | | |
+--+--+--+ |
| |
--- |
__ |
MR>-----------------------+
 
I wanted to ask Fred Bloggs but his mail address is suspicious:

How did you do those ASCII circuts? is there a program that converts
from another format? or do you place each symbol "by hand" as in the
old DOS days?

Fred Bloggs <nospam@nospam.com> wrote in message news:<3F399D9A.2000309@nospam.com>...

snip

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 | |
+-|-------------------|--|--|---+ | +-----------------+
| | | | | | |
| | | | | | __ UF |
CCLK>-+----------------------+ +---------+--------\ \ |
| | | O-------> CO
| +--/__/ |
| 'HCT02 |
__ | |
MR>-----------------------+---------------------------------+


snip
Click to expand...
 
There are modern ASCII art programs that simplify the drawing immensely.
Now you draw lines by dragging the mouse, and most have copy, paste,
and move functions on 2-dimensional blocks of characters that are
selected. In the schematic below I draw one of each component type and
paste a copy where needed. It is as fun as it is easy these days. There
was no conversion from a CAD format.

Abdullah Eyles wrote:
I wanted to ask Fred Bloggs but his mail address is suspicious:

How did you do those ASCII circuts? is there a program that converts
from another format? or do you place each symbol "by hand" as in the
old DOS days?

Fred Bloggs <nospam@nospam.com> wrote in message news:<3F399D9A.2000309@nospam.com>...

snip


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 | |
+-|-------------------|--|--|---+ | +-----------------+
| | | | | | |
| | | | | | __ UF |
CCLK>-+----------------------+ +---------+--------\ \ |
| | | O-------> CO
| +--/__/ |
| 'HCT02 |
__ | |
MR>-----------------------+---------------------------------+



snip
Click to expand...
 
On 14 Aug 2003 04:36:06 -0700, agulesin@hotmail.com (Abdullah Eyles)
wrote:

I wanted to ask Fred Bloggs but his mail address is suspicious:

How did you do those ASCII circuts? is there a program that converts
from another format? or do you place each symbol "by hand" as in the
old DOS days?
Click to expand...
There is also a free offering by Andreas Weber at
http://www.tech-chat.de/ Follow the AACircuit link.

The site is in German but the "language" is electronics so you'll be
able to follow it. The program itself is available in German- and
English-language versions.

--
Rich Webb Norfolk, VA
 
If you are still in search of a long duration timer circuit I happened
across a simple timing circuit.
The primary ic's used for the timing are 1-555, 1-4017B , 1-4020B.
The rest of the circuit uses 6-resisters, 1-pot, 1-rotary switch, 4-caps,
2-diodes , and a transistor.
If you are still searching drop me a line and I'll look into getting the
schematic drawn out for you.
Now you just need a simple display circuit
MAG

"onestone" <onestone@bigpond.net.au> wrote in message
news:Dk2_a.29571$bo1.18142@news-server.bigpond.net.au...
Why are you intentionally making your life difficult? You want to
replace one chip and a couple of hours learning with a couple of
handfuls of chips, days of debugging, and a damn sight more to learn
than with a micro? A wholly pointless excercise unless the objective is
to learn how to design logic circuits.

Al

BM wrote:
Can anyone help point me in the right direction?

I want to make a timer circuit using discreet components (i.e. no pics
or
stamps or inputs from a PC) that will count from 0 when it turns on up
to
9hrs 59mins 59secs. I also want to display the hrs, mins and secs via
7-segment displays. In addition, I would like to be able to freeze and
display the clocks count at any given moment via a hold button.



thanks
Click to expand...
 
Thanks for your help Fred. I've build the circuit that you outlined
and have a couple of follow-up questions.

First is that I've build the first segment (the seconds part)with the
74HCT163 and noticed that it is indeed counting up but it is counting
to 15 and not 9 before resetting. Do I need some sort of 4-bit BIN to
BCD converter to send to the 7447 to correctly drive the 7-seg leds?
Would a 74185 work here?

Also, in regards to the freeze control that you outlined which I've
build and works very well, would simply putting a switch on the clock
input (clock connected when switch up and disconnected when the switch
is down) work as a freeze?

Thanks again for your help.

BM

Fred Bloggs <nospam@nospam.com> wrote in message news:<3F3A3D35.70904@nospam.com>...
This one adds an asynchronous FREEZE control using the remaining 2x
NANDS- action takes effect on inactive negative going clock edge so that
it is glitch proof:

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 | |
+-|-------------------|--|--|---+ | +-----------------+
| | | | | | |
| | | | | | __ 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 | |
+---------------+ |
| | | | |
+--+--+--+ |
| |
--- |
__ |
MR>-----------------------+
Click to expand...
 
Fred Bloggs wrote:
bm wrote:

Thanks for your help Fred. I've build the circuit that you outlined
and have a couple of follow-up questions.

First is that I've build the first segment (the seconds part)with the
74HCT163 and noticed that it is indeed counting up but it is counting
to 15 and not 9 before resetting. Do I need some sort of 4-bit BIN to
BCD converter to send to the 7447 to correctly drive the 7-seg leds?
Would a 74185 work here?


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.


Also, in regards to the freeze control that you outlined which I've
build and works very well, would simply putting a switch on the clock
input (clock connected when switch up and disconnected when the switch
is down) work as a freeze?


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.
Click to expand...
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 |
+-----------+
Click to expand...




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>-----------------------+
 
I think I can but just to be sure, can I mix LS TTLs with HCTs. e.g.
74HCT163 with 74LS00?

Thanks Fred. I'll think I'll tear down the circuit I have and rebuild
it from stratch to make sure I don't have any stupid wirering errors.

BM
 
Yes, you can mix them. The 'T' in 'HCT' means the cmos device is using TTL
input thresholds instead of the wider cmos ones. You can always drive a TTL
input from a cmos output so long as the supplies are the same voltage.

Hope this helps.
Dana Frank Raymond

"bm" <brandon_melland@hotmail.com> wrote in message
news:e95564fd.0308211804.69221324@posting.google.com...
I think I can but just to be sure, can I mix LS TTLs with HCTs. e.g.
74HCT163 with 74LS00?

Thanks Fred. I'll think I'll tear down the circuit I have and rebuild
it from stratch to make sure I don't have any stupid wirering errors.

BM
Click to expand...
 
bm wrote:
I think I can but just to be sure, can I mix LS TTLs with HCTs. e.g.
74HCT163 with 74LS00?
Click to expand...
Yes- that's okay. Change the freeze control like so:

Please view in a fixed-width font such as Courier.


FREEZE CONTROL SCHEMATIC SYMBOL
+------+
| |PEC
|FREEZE|->
| CTL |
+------+
1K
+--/\/\----------------+ 'LS00
| 1K | __
5V >-+--/\/\---------------------+--------------| \
| 10K | | | o-+-->PEC
+--/\/\-+ | | +--|__/ |
| | | | |
| | o run +-|--------+
1Hz | 1000p | | |
CLK >---|<|---+---||----+-------o SW | +--------+
1N4148 | | | \ | |
=== / | o freeze | 'LS00 |
10p 10K | | | __ |
| / | | +----| \ |
| \ | | | o-+
+---------+ +----+--------------|__/
---
com


Thanks Fred. I'll think I'll tear down the circuit I have and rebuild
it from stratch to make sure I don't have any stupid wirering errors.
Click to expand...
The whole counter portion is 5x 74xx163's, 1X 74xx00, 1x 74xx02, and 1x
74xx10. Because the circuit is 100% synchronous and the CLK is a very
low frequency 1Hz, wire lengths and position are not critical at all
except for the CLK line. By sure to place a 0.01u bypass across each
chip between VCC and GND. What construction technique are you using?-
wirewrap, PCB, point-to-point hardwire and sockets on perfboard? And
what is the source and circuit for the 1Hz clock?
 
In article <hDX2b.5406$Jh2.2053
@newsread4.news.pas.earthlink.net>, mcmcm@earthlink.net says...
I know this is off the topic a bit but if you download the free file from
ExpressPCB.com> you can draw a schematic that can be copied and pasted in
to word or word pad, under EDIT you select copy schematic bit map to
clipboard (Could not paste to explorer?) there it can be easily read.
See attached junk word file.
Just a thought.
Click to expand...
....and a *bad* one. Ninaries are *strongly* discouraged on text-
only newsgroups. If you must post a binary do it on a binary
group (like alt.binaries.schematics.electronic). Posting in WORD
format also loses you points.

If you wish to post schematics to a text-only group, may I
suggest AACircuit.

Posting binaries to this group is *RUDE*, to say the least!

--
Keith
 
You must log in or register to reply here.

Welcome to EDABoard.com

Sponsor

Back
Top