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Martin Stefanus · Guest

Hello everyone! I have a question, I hope you can give me a possible
solution to this. I need an IC that reads a binary combination (dip
switch - 8 bit) and the transmit that combination using logic in
serial way. Do you know an IC that does that without any other
supporting IC(s)? The speed does not need to be very high, something
around 9600 bps would do more than fine. Thank you in advance.

Wouter van Ooijen (www.vo · Guest

[quote]Hello everyone! I have a question, I hope you can give me a possible
solution to this. I need an IC that reads a binary combination (dip
switch - 8 bit) and the transmit that combination using logic in
serial way. Do you know an IC that does that without any other
supporting IC(s)? The speed does not need to be very high, something
around 9600 bps would do more than fine. Thank you in advance.
[/quote]
A suitably programmed microcontroller would do this easily.

Wouter van Ooijen

-- ------------------------------------
http://www.voti.nl
PICmicro chips, programmers, consulting

Dave Platt · Guest

[quote]Hello everyone! I have a question, I hope you can give me a possible
solution to this. I need an IC that reads a binary combination (dip
switch - 8 bit) and the transmit that combination using logic in
serial way. Do you know an IC that does that without any other
supporting IC(s)? The speed does not need to be very high, something
around 9600 bps would do more than fine. Thank you in advance.
[/quote]
These days, the easy way to do that would probably be to use a PIC or
similar microcontroller. There>s probably a 14-pin PIC which can run
from an internal R/C oscillator with enough precision to let you hit
9600 bits/second accurately enough to talk to a UART.

--
Dave Platt <dplatt@radagast.org> AE6EO
Hosting the Jade Warrior home page: http://www.radagast.org/jade-warrior
I do _not_ wish to receive unsolicited commercial email, and I will
boycott any company which has the gall to send me such ads!

Mike Harrison · Guest

On 24 Jul 2003 12:05:18 -0700, emails@newmail.net (Martin Stefanus) wrote:

[quote]Hello everyone! I have a question, I hope you can give me a possible
solution to this. I need an IC that reads a binary combination (dip
switch - 8 bit) and the transmit that combination using logic in
serial way. Do you know an IC that does that without any other
supporting IC(s)? The speed does not need to be very high, something
around 9600 bps would do more than fine. Thank you in advance.
[/quote]
A suitably programmed pic16c505 will do this easily and cheaply.

Roger Hamlett · Guest

"Dave Platt" <dplatt@radagast.org> wrote in message
news:vi0ga054k2lcb4@corp.supernews.com...
[quote]Hello everyone! I have a question, I hope you can give me a possible
solution to this. I need an IC that reads a binary combination (dip
switch - 8 bit) and the transmit that combination using logic in
serial way. Do you know an IC that does that without any other
supporting IC(s)? The speed does not need to be very high, something
around 9600 bps would do more than fine. Thank you in advance.

These days, the easy way to do that would probably be to use a PIC or
similar microcontroller. There>s probably a 14-pin PIC which can run
from an internal R/C oscillator with enough precision to let you hit
9600 bits/second accurately enough to talk to a UART.
Look at the PIC16F628. An overkill in a lot of ways, but it has the[/quote]
following features going for it. 18pin package, including a USART built in.
Built in 4MHz oscillator, calibrated to better than 1%. the problem is that
most of the 8pin variants have the oscillator, but the larger chips often
don>t. Obviously the 'minimum' requirement, is 11pins, unless an external
multiplexer is used. Having a built in USART, makes the output a doddle. It
is also remarkably cheap (funnily, the 628, is cheaper than the 627, despite
having twice the memory...). Currently runs at about 2$, in '1 off'.
Programming is also a 'doddle', and simple circuits, can do this with only a
handful of parts necessary.

Best Wishes

Roger Hamlett · Guest

"Mike Harrison" <mike@whitewing.co.uk> wrote in message
news:jfg0ivgh8oognt624icgoo19pvri2u620t@4ax.com...
[quote]On 24 Jul 2003 12:05:18 -0700, emails@newmail.net (Martin Stefanus) wrote:

Hello everyone! I have a question, I hope you can give me a possible
solution to this. I need an IC that reads a binary combination (dip
switch - 8 bit) and the transmit that combination using logic in
serial way. Do you know an IC that does that without any other
supporting IC(s)? The speed does not need to be very high, something
around 9600 bps would do more than fine. Thank you in advance.

A suitably programmed pic16c505 will do this easily and cheaply.
A few years ago, I>d have agreed with you, but the older parts have risen in[/quote]
cost massively compared to the newer reprogrammable parts. The 16C505,
currently lists at $6.25, when the much more powerful (and reprogrammable -
better for development 16F627-04), is listing at $1.81 from the same
supplier.
It is well worth looking at the newer PICs, there prices are much more
aggressive. :-)

Best Wishes

Watson A.Name - 'Watt Sun · Guest

In article <vi0ga054k2lcb4@corp.supernews.com>, dplatt@radagast.org
mentioned...
[quote]Hello everyone! I have a question, I hope you can give me a possible
solution to this. I need an IC that reads a binary combination (dip
switch - 8 bit) and the transmit that combination using logic in
serial way. Do you know an IC that does that without any other
supporting IC(s)? The speed does not need to be very high, something
around 9600 bps would do more than fine. Thank you in advance.

These days, the easy way to do that would probably be to use a PIC or
similar microcontroller. There>s probably a 14-pin PIC which can run
from an internal R/C oscillator with enough precision to let you hit
9600 bits/second accurately enough to talk to a UART.
[/quote]
I tore apart a mouse recently that didn>t have the usual resonator,
all it had was a 1% resistor. So apparently they use some internal
capacitance and the resistor to generate the clock with enough
accuracy to give the mouse baudrate of 1200 baud.

I suppose one could build it out of a CMOS parallel in, serial out
chip like the 4014 or 4021, but it would take other chips, too.

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http://www.everybookstore.com You>ll be glad you did!
Just when you thought you had all this figured out, the gov>t
changed it: http://physics.nist.gov/cuu/Units/binary.html
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Mike Harrison · Guest

On Thu, 24 Jul 2003 23:48:53 -0700, Watson A.Name - 'Watt Sun' <alondra101@hotmail.com> wrote:

[quote]In article <vi0ga054k2lcb4@corp.supernews.com>, dplatt@radagast.org
mentioned...
Hello everyone! I have a question, I hope you can give me a possible
solution to this. I need an IC that reads a binary combination (dip
switch - 8 bit) and the transmit that combination using logic in
serial way. Do you know an IC that does that without any other
supporting IC(s)? The speed does not need to be very high, something
around 9600 bps would do more than fine. Thank you in advance.

These days, the easy way to do that would probably be to use a PIC or
similar microcontroller. There>s probably a 14-pin PIC which can run
from an internal R/C oscillator with enough precision to let you hit
9600 bits/second accurately enough to talk to a UART.

I tore apart a mouse recently that didn>t have the usual resonator,
all it had was a 1% resistor. So apparently they use some internal
capacitance and the resistor to generate the clock with enough
accuracy to give the mouse baudrate of 1200 baud.
[/quote]
Not necessarily - it could be calibrating against an incoming data byte.

Roger Hamlett · Guest

"Mike Harrison" <mike@whitewing.co.uk> wrote in message
news:dpt1ivkq1siv5p6mad0nkni5cpo7b0vk85@4ax.com...
[quote]On Thu, 24 Jul 2003 22:47:15 +0100, "Roger Hamlett"
rogerspamignored@ttelmah.demon.co.uk> wrote:

"Mike Harrison" <mike@whitewing.co.uk> wrote in message
news:jfg0ivgh8oognt624icgoo19pvri2u620t@4ax.com...
On 24 Jul 2003 12:05:18 -0700, emails@newmail.net (Martin Stefanus)
wrote:

Hello everyone! I have a question, I hope you can give me a possible
solution to this. I need an IC that reads a binary combination (dip
switch - 8 bit) and the transmit that combination using logic in
serial way. Do you know an IC that does that without any other
supporting IC(s)? The speed does not need to be very high, something
around 9600 bps would do more than fine. Thank you in advance.

A suitably programmed pic16c505 will do this easily and cheaply.
A few years ago, I>d have agreed with you, but the older parts have risen
in
cost massively compared to the newer reprogrammable parts. The 16C505,
currently lists at $6.25, when the much more powerful (and
reprogrammable -
better for development 16F627-04), is listing at $1.81 from the same
supplier.
It is well worth looking at the newer PICs, there prices are much more
aggressive. :-)

www.findchips.com shows prices wown to $1.33 for 16c505. and $1.68 for
16F627.

The newer ones are certainly good value, but if you don>t need their extra
functions, the older
parts can often be cheaper for production.
Did you actually check stock on the suppliers listing the 16C505 at this[/quote]
price?. I found two suppliers with cheap prices listed for the 505, but
neither showed stock. The $6.25, was on a quick search, the lowest price I
could see, where the supplier actually had the chips. I was also looking for
'one off' availability, since unless I read the question wrong, I don>t
think the original enquirer is after 1000 off prices (the findchip prices
are normally for bulk quantities). At the 'low run' end of the market, the
older parts have a premium price. Also, the 'source' prices of these parts
have shot up in the last couple of months, so the suppliers offering these
at low prices, are probably shifting old stock (hence my comment), and I
have to suspect that production now is in relatively small small batches
with massive price variations as these become available.

Best Wishes

Wouter van Ooijen (www.vo · Guest

[quote]These days, the easy way to do that would probably be to use a PIC or
similar microcontroller. There>s probably a 14-pin PIC which can run
from an internal R/C oscillator with enough precision to let you hit
9600 bits/second accurately enough to talk to a UART.
[/quote]
The 16F630 has an internall OSC and it will probably work, but from
the worst case figures you should not rely on it. Add a cheap crystal
or resonator.

PS in my webshop a16F630 + Xtal ~ E 3.00 (plus S/H).

Wouter van Ooijen

-- ------------------------------------
http://www.voti.nl
PICmicro chips, programmers, consulting

Wouter van Ooijen (www.vo · Guest

[quote]www.findchips.com shows prices wown to $1.33 for 16c505. and $1.68 for 16F627.

The newer ones are certainly good value, but if you don>t need their extra functions, the older
parts can often be cheaper for production.
[/quote]
I did not get the impression that the OP was aiming at 1k+ units :)

Wouter van Ooijen

-- ------------------------------------
http://www.voti.nl
PICmicro chips, programmers, consulting

Wouter van Ooijen (www.vo · Guest

[quote]Why does everyone nowadays insist on using a PIC to do absolutely anything,
however simple? You have to program the thing, worry about which one to use,
etc etc. This simple requirement would be satisfied by just 2 ordinary logic
IC>s. Just connect them up and they go, no programming. Yes you *could* do
it with a PIC. If you weren>t already a PIC expert, waste of time. Even for
a PIC expert, I doubt you>d be able to get it working as quickly as the
simple 2-logic-chip version. The 2 logic chips almost certainly cheaper than
a PIC too!
[/quote]
The OP mentioned something about 9600 baud, which suggests to me that
he probably wants asynch serial data, which would not be so easy using
TTL.

I cannot comment for a non-PIC expert, but maybe you forget that a
PIC-expert is (by lazyness, maybe) probably not as expert in using TTL
chips. For me writing the program to send the data would probably take
a few minutes to write and a few more to debug. In fact, this would
probably be the program for a 16F630:

include f675_20 -- no 16F630/676 support yet, use 12F675
include jlib

port_a_direction = all_output
port_c_direction = all_input

const asynch_baudrate = 9600
const asynch_polarity = active_high
const asynch_parity = parity_none
const asynch_stopbits = 2

var volatile bit asynch_in_pin is pin_a0
var volatile bit asynch_in_direction is pin_a0_direction

var volatile bit asynch_out_pin is pin_a1
var volatile bit asynch_out_direction is pin_a1_direction

include seriali

forever loop
delay_100ms( 5 )
asynch_send( port_a )
end loop

Wouter van Ooijen

-- ------------------------------------
http://www.voti.nl
PICmicro chips, programmers, consulting

Mark (UK) · Guest

Hiya!

Okay, as we>re suggesting programs, here>s some code I cooked up for
using a GAL for the same purpose - 8 bits in, transmitting an 8-N-1
serial stream (in CUPL):

Device g22v10;

/** Inputs **/

Pin 1 = d0;
Pin 2 = d1;
Pin 3 = d2;
Pin 4 = d3;
Pin 5 = d4;
Pin 6 = d5;
Pin 7 = d6;
Pin 8 = d7;
Pin 9 = a0;
Pin 10 = a1;
Pin 11 = a2;
Pin 13 = a3;

/** Outputs **/

Pin 19 = so; /** Serial output **/
Pin 18 = sr; /** Synchronous Reset **/

/** main **/

sr = a3 & !a2 & !a1 & a0;

/** 8-N-1 equation, others could be specified **/

so = (!a3 & !a2 & !a1 & !a0 & 'b>0) #
(!a3 & !a2 & !a1 & a0 & d0) #
(!a3 & !a2 & a1 & !a0 & d1) #
(!a3 & !a2 & a1 & a0 & d2) #
(!a3 & a2 & !a1 & !a0 & d3) #
(!a3 & a2 & !a1 & a0 & d4) #
(!a3 & a2 & a1 & !a0 & d5) #
(!a3 & a2 & a1 & a0 & d6) #
(a3 & !a2 & !a1 & !a0 & d7) #
(a3 & !a2 & !a1 & a0 & 'b>1);

Okay, maybe not as cheap as a pic (especially as you need a 22v10), and
you>d need a sync. resetable counter, and an oscillator, but it just
shows another way. The equation could be altered for other stop bits,
and a parity equation could be written as well.

Yours, Mark.

"Wouter van Ooijen (www.voti.nl)" wrote:
[quote]
Why does everyone nowadays insist on using a PIC to do absolutely anything,
however simple? You have to program the thing, worry about which one to use,
etc etc. This simple requirement would be satisfied by just 2 ordinary logic
IC>s. Just connect them up and they go, no programming. Yes you *could* do
it with a PIC. If you weren>t already a PIC expert, waste of time. Even for
a PIC expert, I doubt you>d be able to get it working as quickly as the
simple 2-logic-chip version. The 2 logic chips almost certainly cheaper than
a PIC too!

The OP mentioned something about 9600 baud, which suggests to me that
he probably wants asynch serial data, which would not be so easy using
TTL.

I cannot comment for a non-PIC expert, but maybe you forget that a
PIC-expert is (by lazyness, maybe) probably not as expert in using TTL
chips. For me writing the program to send the data would probably take
a few minutes to write and a few more to debug. In fact, this would
probably be the program for a 16F630:

include f675_20 -- no 16F630/676 support yet, use 12F675
include jlib

port_a_direction = all_output
port_c_direction = all_input

const asynch_baudrate = 9600
const asynch_polarity = active_high
const asynch_parity = parity_none
const asynch_stopbits = 2

var volatile bit asynch_in_pin is pin_a0
var volatile bit asynch_in_direction is pin_a0_direction

var volatile bit asynch_out_pin is pin_a1
var volatile bit asynch_out_direction is pin_a1_direction

include seriali

forever loop
delay_100ms( 5 )
asynch_send( port_a )
end loop

Wouter van Ooijen

-- ------------------------------------
http://www.voti.nl
PICmicro chips, programmers, consulting[/quote]

Mark (UK) · Guest

Hi (to myself!)

Actually, I>ve just thought, the counter could be written into the GAL
as well, so you>d only need an external oscillator. Would have to change
a few of the pinouts around though....

Yours, Mark.

"Mark (UK)" wrote:
[quote]
Hiya!

Okay, as we>re suggesting programs, here>s some code I cooked up for
using a GAL for the same purpose - 8 bits in, transmitting an 8-N-1
serial stream (in CUPL):

Device g22v10;

/** Inputs **/

Pin 1 = d0;
Pin 2 = d1;
Pin 3 = d2;
Pin 4 = d3;
Pin 5 = d4;
Pin 6 = d5;
Pin 7 = d6;
Pin 8 = d7;
Pin 9 = a0;
Pin 10 = a1;
Pin 11 = a2;
Pin 13 = a3;

/** Outputs **/

Pin 19 = so; /** Serial output **/
Pin 18 = sr; /** Synchronous Reset **/

/** main **/

sr = a3 & !a2 & !a1 & a0;

/** 8-N-1 equation, others could be specified **/

so = (!a3 & !a2 & !a1 & !a0 & 'b>0) #
(!a3 & !a2 & !a1 & a0 & d0) #
(!a3 & !a2 & a1 & !a0 & d1) #
(!a3 & !a2 & a1 & a0 & d2) #
(!a3 & a2 & !a1 & !a0 & d3) #
(!a3 & a2 & !a1 & a0 & d4) #
(!a3 & a2 & a1 & !a0 & d5) #
(!a3 & a2 & a1 & a0 & d6) #
(a3 & !a2 & !a1 & !a0 & d7) #
(a3 & !a2 & !a1 & a0 & 'b>1);

Okay, maybe not as cheap as a pic (especially as you need a 22v10), and
you>d need a sync. resetable counter, and an oscillator, but it just
shows another way. The equation could be altered for other stop bits,
and a parity equation could be written as well.

Yours, Mark.

"Wouter van Ooijen (www.voti.nl)" wrote:

Why does everyone nowadays insist on using a PIC to do absolutely anything,
however simple? You have to program the thing, worry about which one to use,
etc etc. This simple requirement would be satisfied by just 2 ordinary logic
IC>s. Just connect them up and they go, no programming. Yes you *could* do
it with a PIC. If you weren>t already a PIC expert, waste of time. Even for
a PIC expert, I doubt you>d be able to get it working as quickly as the
simple 2-logic-chip version. The 2 logic chips almost certainly cheaper than
a PIC too!

The OP mentioned something about 9600 baud, which suggests to me that
he probably wants asynch serial data, which would not be so easy using
TTL.

I cannot comment for a non-PIC expert, but maybe you forget that a
PIC-expert is (by lazyness, maybe) probably not as expert in using TTL
chips. For me writing the program to send the data would probably take
a few minutes to write and a few more to debug. In fact, this would
probably be the program for a 16F630:

include f675_20 -- no 16F630/676 support yet, use 12F675
include jlib

port_a_direction = all_output
port_c_direction = all_input

const asynch_baudrate = 9600
const asynch_polarity = active_high
const asynch_parity = parity_none
const asynch_stopbits = 2

var volatile bit asynch_in_pin is pin_a0
var volatile bit asynch_in_direction is pin_a0_direction

var volatile bit asynch_out_pin is pin_a1
var volatile bit asynch_out_direction is pin_a1_direction

include seriali

forever loop
delay_100ms( 5 )
asynch_send( port_a )
end loop

Wouter van Ooijen

-- ------------------------------------
http://www.voti.nl
PICmicro chips, programmers, consulting[/quote]

Fred Abse · Guest

On Thu, 24 Jul 2003 20:05:18 +0100, Martin Stefanus wrote:

[quote]Hello everyone! I have a question, I hope you can give me a possible
solution to this. I need an IC that reads a binary combination (dip
switch - 8 bit) and the transmit that combination using logic in serial
way. Do you know an IC that does that without any other supporting
IC(s)? The speed does not need to be very high, something around 9600
bps would do more than fine. Thank you in advance.
[/quote]
A UART?

--
Then there>s duct tape ...
(Garrison Keillor)
nofr@sbhevre.pbzchyvax.pb.hx


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