"xpyttl" wrote in message
...
"Tim Wescott" wrote in message
...

But first the obligitory assesment of assumptions: Why are LCD displays
not
an option? Could you drive an LCD from your PIC? I've seen info on
this
from the LCD manufacturers; it looks quite doable from a PIC.

I was wondering that myself. It's a whole bunch lower power than LEDs,
which seemed to be a requirement, and the circuitry is a pile simpler.
The
one requirement he did have was "durability" that maybe you could argue
LEDs
had a leg up on. Well, maybe with those teeny LED displays you could keep
the size smaller than an LCD, but I suspect you would more than make up
for
it in drive circuitry, unless maybe he's thinking surface mount.

Oh, and driving an LCD is a piece of cake from a PIC.

..I appreciate all the comments. The glass cases of the LCD- aside from
being large, is a bit fragile. This is going in a very small trail ready
radio- that may have to survive falls from 3000' rock cliffs. Already lost
an LCD that way.

Dale W4OP

In article , "Tim Wescott"
writes:

Hey! I think I have some of those. Since I'm never going to use them, I
suppose I could part with them.

But first the obligitory assesment of assumptions: Why are LCD displays not
an option? Could you drive an LCD from your PIC? I've seen info on this
from the LCD manufacturers; it looks quite doable from a PIC.

You are asking the wrong person. I was responding to the person
saying "LCDs are not an option."

An LCD display assembly can most certainly be "driven" (input the
ASCII code for the character) from a PIC. That is how nearly all of
the little wattmeters and frequency counters are arranged.

Actual DRIVE for an LCD takes a different waveform for most LCD
panels. Some are 2-level, others 3-level in their waveform voltages.
Research the LCD display alone, without the local memory and
scan-drive hardware. That part is not as straightforward as it looks.

A PIC PROGRAM normally scans through an internal register
content and outputs based on that. Usually there is a small conversion
operation to change the code from 4-bit numeric to 8-bit ASCII. That
scanning-and-outputting part of the program can easily be changed
(if you know how to write with the free PIC development program) to
"strobe" an LED array, segments versus character position.

If you don't know how to change an already burned-in PIC, then you
must have some sort of outboard local memory to hold 4-bit chunks
of numeric data...or convert from 8-bit ASCII to two 4-bit BCD in order
to drive a 7-bar segment decoder-driver that CAN drive a numeric LED.
That requires more ICs, one decoder-driver per numeral. Average power
to light the LED is about the same for any given brightness whether it
is driven on a DC basis or strobed segment v. numeral.

NONE of the above is "trivial" nor any sort of "cake" if you've never
worked with microcontrollers or their development systems before.
Almost ANYTHING "doable" can be done but development time and
resulting learning curves are hard to fund at the home hobbyist level.

For example, I've been working on inventing anti-gravity. Something
keeps holding the project down ...

Len Anderson
retired (from regular hours) electronic engineer person

In article , "Tim Wescott"
writes:

Hey! I think I have some of those. Since I'm never going to use them, I
suppose I could part with them.

But first the obligitory assesment of assumptions: Why are LCD displays not
an option? Could you drive an LCD from your PIC? I've seen info on this
from the LCD manufacturers; it looks quite doable from a PIC.

You are asking the wrong person. I was responding to the person
saying "LCDs are not an option."

An LCD display assembly can most certainly be "driven" (input the
ASCII code for the character) from a PIC. That is how nearly all of
the little wattmeters and frequency counters are arranged.

Actual DRIVE for an LCD takes a different waveform for most LCD
panels. Some are 2-level, others 3-level in their waveform voltages.
Research the LCD display alone, without the local memory and
scan-drive hardware. That part is not as straightforward as it looks.

A PIC PROGRAM normally scans through an internal register
content and outputs based on that. Usually there is a small conversion
operation to change the code from 4-bit numeric to 8-bit ASCII. That
scanning-and-outputting part of the program can easily be changed
(if you know how to write with the free PIC development program) to
"strobe" an LED array, segments versus character position.

If you don't know how to change an already burned-in PIC, then you
must have some sort of outboard local memory to hold 4-bit chunks
of numeric data...or convert from 8-bit ASCII to two 4-bit BCD in order
to drive a 7-bar segment decoder-driver that CAN drive a numeric LED.
That requires more ICs, one decoder-driver per numeral. Average power
to light the LED is about the same for any given brightness whether it
is driven on a DC basis or strobed segment v. numeral.

NONE of the above is "trivial" nor any sort of "cake" if you've never
worked with microcontrollers or their development systems before.
Almost ANYTHING "doable" can be done but development time and
resulting learning curves are hard to fund at the home hobbyist level.

For example, I've been working on inventing anti-gravity. Something
keeps holding the project down ...

Len Anderson
retired (from regular hours) electronic engineer person

Dale Parfitt wrote:


..I appreciate all the comments. The glass cases of the LCD- aside from

being large, is a bit fragile. This is going in a very small trail ready
radio- that may have to survive falls from 3000' rock cliffs. Already lost
an LCD that way.

Dale W4OP

Wow
I suspect not much would survive that sort of fall
My counter at http://members.iinet.net.au/~richardh/VK6BRO.htm
takes less than 10 mA
The LCD module is probably as rugged as a LED setup, particularly if you
have to mount individual displays and drivers opn a board
Unfortunately I have sold all the current boards but the software and
circuitry is there.
It uses a AVR rather than a PIC

Richard

Dale Parfitt wrote:


..I appreciate all the comments. The glass cases of the LCD- aside from

being large, is a bit fragile. This is going in a very small trail ready
radio- that may have to survive falls from 3000' rock cliffs. Already lost
an LCD that way.

Dale W4OP

Wow
I suspect not much would survive that sort of fall
My counter at http://members.iinet.net.au/~richardh/VK6BRO.htm
takes less than 10 mA
The LCD module is probably as rugged as a LED setup, particularly if you
have to mount individual displays and drivers opn a board
Unfortunately I have sold all the current boards but the software and
circuitry is there.
It uses a AVR rather than a PIC

Richard

At first I thought you wanted a counter, but it sounds more like a frequency
display for a rig is what you are looking for.

If you're madly in love with LEDs, you may want something like that one
digit counter that I think was in QST a few years back. Understand that
LEDs are current hungry and require relatively complex support circuitry
compared to LCDs. You can reduce both of these by cutting down the number
of digits. You can also add some complexity, either in software or
circuitry, to help with the current drain, but finding something that will
likely work with your radio is improbable .. to get the combination you are
going to have to do some of the design work yourself. You will also be
challenged in trading off the current for brightness. I suspect (can't say
I know for sure) that making an LED display work at low current at a
brightness level you could use outdoors in the daytime is going to be
something of a problem.

That being said, what about something like Dave Fifield's AFA or Dave
Benson's Freq-Mite? This gets you way smaller and lighter than your LEDs,
and certainly no less durable. And the current consumption will be orders
of magnitude less than even the most carefully implemented LEDs. You don't
get the warm, red glow, but you get the frequency in a fraction of the
size/weight/current. And for twenty bucks you avoid the whole design/parts
procurement exercise.

...

"Dale Parfitt" wrote in message
...

"xpyttl" wrote in message
...
"Tim Wescott" wrote in message
...

But first the obligitory assesment of assumptions: Why are LCD
displays
not
an option? Could you drive an LCD from your PIC? I've seen info on
this
from the LCD manufacturers; it looks quite doable from a PIC.

I was wondering that myself. It's a whole bunch lower power than LEDs,
which seemed to be a requirement, and the circuitry is a pile simpler.
The
one requirement he did have was "durability" that maybe you could argue
LEDs
had a leg up on. Well, maybe with those teeny LED displays you could
keep
the size smaller than an LCD, but I suspect you would more than make up
for
it in drive circuitry, unless maybe he's thinking surface mount.

Oh, and driving an LCD is a piece of cake from a PIC.

..I appreciate all the comments. The glass cases of the LCD- aside from
being large, is a bit fragile. This is going in a very small trail ready
radio- that may have to survive falls from 3000' rock cliffs. Already lost
an LCD that way.

Dale W4OP

At first I thought you wanted a counter, but it sounds more like a frequency
display for a rig is what you are looking for.

If you're madly in love with LEDs, you may want something like that one
digit counter that I think was in QST a few years back. Understand that
LEDs are current hungry and require relatively complex support circuitry
compared to LCDs. You can reduce both of these by cutting down the number
of digits. You can also add some complexity, either in software or
circuitry, to help with the current drain, but finding something that will
likely work with your radio is improbable .. to get the combination you are
going to have to do some of the design work yourself. You will also be
challenged in trading off the current for brightness. I suspect (can't say
I know for sure) that making an LED display work at low current at a
brightness level you could use outdoors in the daytime is going to be
something of a problem.

That being said, what about something like Dave Fifield's AFA or Dave
Benson's Freq-Mite? This gets you way smaller and lighter than your LEDs,
and certainly no less durable. And the current consumption will be orders
of magnitude less than even the most carefully implemented LEDs. You don't
get the warm, red glow, but you get the frequency in a fraction of the
size/weight/current. And for twenty bucks you avoid the whole design/parts
procurement exercise.

...

"Dale Parfitt" wrote in message
...

"xpyttl" wrote in message
...
"Tim Wescott" wrote in message
...

But first the obligitory assesment of assumptions: Why are LCD
displays
not
an option? Could you drive an LCD from your PIC? I've seen info on
this
from the LCD manufacturers; it looks quite doable from a PIC.

I was wondering that myself. It's a whole bunch lower power than LEDs,
which seemed to be a requirement, and the circuitry is a pile simpler.
The
one requirement he did have was "durability" that maybe you could argue
LEDs
had a leg up on. Well, maybe with those teeny LED displays you could
keep
the size smaller than an LCD, but I suspect you would more than make up
for
it in drive circuitry, unless maybe he's thinking surface mount.

Oh, and driving an LCD is a piece of cake from a PIC.

..I appreciate all the comments. The glass cases of the LCD- aside from
being large, is a bit fragile. This is going in a very small trail ready
radio- that may have to survive falls from 3000' rock cliffs. Already lost
an LCD that way.

Dale W4OP

"Avery Fineman" wrote in message
...
In article , "Tim Wescott"
writes:

NONE of the above is "trivial" nor any sort of "cake" if you've never
worked with microcontrollers or their development systems before.
Almost ANYTHING "doable" can be done but development time and
resulting learning curves are hard to fund at the home hobbyist level.

Au contraire!

Well, I suppose if you are scared to death of solid state electronics and
computers, then perhaps it's really hard. But in this day and age a huge
fraction, bordering on most, amateur radio projects involve some sort of
microcontroller. This isn't some comspiracy, they make the whole project
simpler, less expensive, and more flexible.

Granted, there is a learning curve if you've never done it before, but I
would expect that someone who wasn't totally terrified could learn enough to
make the sorts of changes he might need to an off the shelf project, build
the programming hardware, and get the project working in less
time/effort/money than simply getting a reasonable number of LED digits
wired and driven!

...

"Avery Fineman" wrote in message
...
In article , "Tim Wescott"
writes:

NONE of the above is "trivial" nor any sort of "cake" if you've never
worked with microcontrollers or their development systems before.
Almost ANYTHING "doable" can be done but development time and
resulting learning curves are hard to fund at the home hobbyist level.

Au contraire!

Well, I suppose if you are scared to death of solid state electronics and
computers, then perhaps it's really hard. But in this day and age a huge
fraction, bordering on most, amateur radio projects involve some sort of
microcontroller. This isn't some comspiracy, they make the whole project
simpler, less expensive, and more flexible.

Granted, there is a learning curve if you've never done it before, but I
would expect that someone who wasn't totally terrified could learn enough to
make the sorts of changes he might need to an off the shelf project, build
the programming hardware, and get the project working in less
time/effort/money than simply getting a reasonable number of LED digits
wired and driven!

...

In article , "xpyttl"
writes:

"Avery Fineman" wrote in message
...
In article , "Tim Wescott"
writes:

NONE of the above is "trivial" nor any sort of "cake" if you've never
worked with microcontrollers or their development systems before.
Almost ANYTHING "doable" can be done but development time and
resulting learning curves are hard to fund at the home hobbyist level.

Au contraire!

Well, I suppose if you are scared to death of solid state electronics and
computers, then perhaps it's really hard.

Not I. Made my living, paid the bills for over four decades plus using,
designing with semiconductors. :-)

Try a dose of realistic thinking in terms of hardware, based on the
time available for hobby projects. Time. That most precious of all
personal commodities.

Programming a microcontroller is not trivial. It requires a new skill,
of outlining a sequence of events governed by decision points of
states, of (at least) being familiar with instructions/commands
recognized by the micro. While the PIC development program is
free, the ability to use the program is not automatic in download.
One MUST become familiar with "Assembler level" programming, of
including every single sequential command and decision point needed
by the program application. Having done that sort of thing primarily
for hobby purposes for over two decades, I find it both fun and
fascinating in total control of a micro's actions. My only complaint
there is that there is no standardization of instructions between
manufacturers...the "dialects" require small learning curves each time
there is a switch of micro families.

The most convenient was to apply a microprocessor or micro-
controller is to get one with the program already burned in. Saves an
enormous amount of development time...but does not do any good for
personal programming experience, only in the installation of the micro.

It's hard to beat the AADE unit (available for any conversion scheme,
direct- to triple-conversion) for applying a relatively cheap ready-built
to a frequency indicator. www.aade.com

But in this day and age a huge
fraction, bordering on most, amateur radio projects involve some sort of
microcontroller.

Yes and no. :-) That depends on the source of information for the
project. Magazines don't like to include pages of a PIC program since
those require many pages of expensive paper (which needs advertising
space sold to make it "cheap"). It isn't immediately flashy and the
program writers don't always include Comments in source code
sufficient to make the program flow clear at first reading.

Ready-built, off-the-shelf amateur radio equipment DOES use one or
more microcontrollers internally. You cannot truly qualify that "most"
hobby projects use them. :-)

This isn't some comspiracy, they make the whole project
simpler, less expensive, and more flexible.

Totally agreed. However, in fairness, use of a microcontroller in a
ham project is NOT traditional analog circuitry (that some old-timers
insist is the "only" kind of "radio"). It does NOT exemplify the mass
of mechanical structures used in 3 and 4 decade old project pictures
looked at many times in old handbooks...looked at in emotional awe
and wonderment. Microcontrollers are NOT traditional components
and have functions unrelated to physical mechanics that they often
replace. Different. Minds have to adapt to NEW ways to do things.

Granted, there is a learning curve if you've never done it before, but I
would expect that someone who wasn't totally terrified could learn enough to
make the sorts of changes he might need to an off the shelf project, build
the programming hardware, and get the project working in less
time/effort/money than simply getting a reasonable number of LED digits
wired and driven!

Of course. :-) The pep-rally over-confidence syndrome...one can do
anything with a "positive outlook"...immediately...no problems at all,
right? :-)

In a remote way, yes. Unknowns are not a "terror" to everyone. They
should be just things unknown that must be learned in order to apply
them. That takes some skull sweat at becoming familiar and such
study takes TIME. Such learning time seldom provides immediate
solutions to a present project but it has incalculable worth in being
able to apply the micro techniques to all sorts of future problems.

Why bash anyone for wanting to use LEDs instead of LCDs? There
are advantages to each kind of display. For a personal project, I
would think that it is up to the individual to determine individual
desires. Is there something "wrong" with individualism? I think not.

I'm working on inventing anti-gravity...but something's holding the
project down.

Len Anderson
retired (from regular hours) electronic engineer person