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'[PIC]: [PBK] The PICLIST Beginners Kit Brief'
2002\09\05@122418
by
Alan B. Pearce
This is long, so if you do not wish to be involved in the Pic beginners Kit,
you may wish to discard this.
This is my general discussion document for where I see the PIC Beginners
Kit heading as a project. There are further comments in paragraphs at the
bottom on why I have made some these choices. This is not to say that any
item here is a "done deal", but rather a way of getting all info into one
place.
I have included paragraph numbers to attempt to make it easier to discuss
points. At times this starts to sound like a cop show on TV :)
Some of the points need re-ordering into other paragraphs to properly sort
items together, but hey, this was thrown together when I should have been
doing something else :)
Later paragraphs dealing with software are my attempt at a specification of
what will be required. This does not necessarily mean that it will get done.
This release to be known as version 1 Pic Beginners Kit Brief,
released 5 Sept 2002. I include this so that as alterations occur, it is
possible to track which version of the brief people refer to.
1. General Aims
1.1 Provide already built development environment for PIC Beginners.
1.2 Programmer and PC interface provided on board. This chip is
referred to as iPIC (Interface PIC) within this brief.
Chip used to be 16F877A or 18F452.
1.3 Two sockets for microprocessors using 16F877A or 18F452.
Other processors using Microchips' "standard footprint"
(Microchip term) may be accommodated at a later date.
Processors will be referred to as "Target 1" and "Target 2"
within this brief.
1.4 One USB and two serial interfaces available to communicate
with external host PC(s).
1.5 Some minimal display hardware on board for programming exercises
with peripherals, and for debug indicator use.
1.6 Some minimal digital input hardware to allow experimentation
with programs. Examples as in following sub paragraphs.
1.6.1 Push button switches. Suggest four switches to allow up/down,
reset, clock setting type experimentation.
1.6.2 Rotary encoder to allow experimenting with value/voltage
adjust experiments.
1.7 Separate push button reset switches to be provided for
Target 1 and Target 2.
1.8 Further access to I/O ports using virtual peripherals accessed
from PC Interface. Virtual inputs to include reset functions for
Target1 and Target2.
1.9 Some minimal analogue hardware to allow analogue experimentation.
Op-amps to buffer analogue impedances into the ADC to be provided.
These are to have sufficient protection resistors to prevent damage
to the PIC from inadvertent over voltage being applied.
Suggestions in following sub paragraphs.
1.9.1 LM35 type temperature sensor, or similar which has voltage
output.
1.9.2 Standard potentiometer for manual analogue input.
1.9.3 LM3919 type bargraph for analogue voltage display connected
to PWM output, or monitoring potentiometer.
1.10 External ICSP connector to be available to program "off board"
PIC's. (Off Board processors to be referred to as "Target 3")
2. Interfaces
2.1 Primary interface for programmer (as delivered) to be USB COM port.
2.2 Programmer to be jumper settable to Serial 1 port as alternative
at 19.2k baud.
2.3 Primary Interface for Target 1 processor to be Serial 1, switchable
to USB or Serial 2.
2.4 Primary interface for Target 2 processor to be Serial 2, switchable
to USB.
2.5 Digital display hardware to consist of bargraph display and 4 digit,
7 segment display.
2.5.1 Bargraph display to be 8 bars, using ULN2803 as driver,
allowing open inputs without damage. It may be possible to
utilise a full 10 bar display if spare drivers exist in
another ULN2803 package, as it seems that 10 bars is the
standard LED bar graph package.
2.5.2 Seven segment display arranged to require multiplexed digits.
Four digits with decimal points, and possibly colon (for clock
use) if available (See 9.3 possible candidate). Current Sink
drivers to be ULN2803 type, digit source driver TBD.
2.6 Virtual digital monitoring to be handled by Parallel In - Serial Out
shift registers, permanently attached to port bits on both Target 1
and Target 2 processor. Where necessary jumpers and/or protection
resistors to be fitted to prevent problems within the shift
registers on ports available for analogue use.
2.7 Virtual digital input to the target processors limited to 16 bits,
jumperable to individual pins on either processor.
2.8 All virtual digital I/O shift registers accessed using SPI port on
iPIC. This information is supplied to the host PC for display using
program provided with hardware. Output SIPO register suggested as
74HC595 and monitor PISO registers suggested as 74HC573/4.
2.9 Programming port to be selectable under software from the host PC.
High voltage programming to be supported using on board generator.
2.10 Power to be supplied from a "Wall Wart" supply, with rectifier and
regulator circuitry allowing a wide range of AC or DC input sources.
My default connector for this is a 2.5mm type as used by Microchip
on the Picstart Plus and other items that they supply using the
universal switchmode supply.
2.11 Breadboard area to be provided using "measles array" of solder pads
on 0.1" centres. Area to cover all otherwise unused space on PCB.
Pads to be provided on edge of PCB for DIN 41612 connector, or 40
pin IDC ribbon cable header. Neither type of connector supplied with
kit.
2.12 Both target processors provided with pins for making connections to
breadboard area, or off board connections.
3 Interface Processor
3.1 The iPIC to be a 16F877A, but it may be that an 18F452 would be a
better choice. This could be left to the person writing the
software, as the footprint of the two processors is the same.
3.2 The processor to have a bootloader to allow for easy update of the
internal software.
3.3 The iPIC to communicate at a standard baud rate, irrespective of USB
or serial connection. This may mean any example software provided
for the target processors would need to be operated at the same baud
rate as it would not be known if the target is to operate on the
serial or USB interface, and the USB driver would need to be set to
a known speed for the iPIC.
3.4 The iPIC to control the generation of high voltage for programming.
The decision to use the internal PWM hardware to drive a boost
circuit in the manner of the ICD1, or use an external boost
regulator is yet to be made. If the internal PWM hardware is used, I
suggest that it be made a closed loop system using an ADC channel to
monitor the voltage and control the PWM.
3.5 The iPIC should software select the target to be programmed, rather
than use hardware jumpers for selection. This will need to include
switching the high voltage programming voltage to the selected
target.
3.6 A PWM port should be used to provide a "virtual analogue source" for
testing programs on a target processor. Connection to be by jumper
wire.
3.7 At least one ADC to be available as a "virtual analogue monitor" for
connection to target processor circuits. Connection to be by jumper
wire.
3.8 The iPIC programming software will need to be able to handle 16F87x,
18Fxxx and 16F62x processors as a minimum design requirement. Once
software is stable, addition of other processors can be considered
as room in the internal ROM allows.
3.9 A software facility to copy software from Target 1 to Target 2, or
from either Target 1 or Target 2 to the target 3 ICSP port be
available. This is in addition to downloading from the host PC.
3.10 The iPIC be able to be a "virtual serial port" to any of the target
processor ports, using the RB6 and RB7 programming pins on the
target chips for bit bash serial I/O. This would only be available
where the target is not in debug mode, and will require a protocol
to allow multiple target information transfer to the host PC through
the iPIC.
4. Target 1 Processor.
4.1 A socket is provided to take a 40 pin DIP version of a 16F877,
16F877A or 18F452. Consideration will need to be given to supporting
later processor announcements by Microchip, as they seem to have
used this pinout as a standard foot print, and refer to it as such
in their literature. A programmed 16F877A to be provided already
fitted in this position.
4.2 The "as shipped" kit to have the hardware I/O jumpered to suitable
pins so the program in the chip will allow demonstration of the I/O
functions of both hardware and virtual I/O without any operations
being required on the board by the user.
4.3 The processor shipped to be loaded with program that exercises the
hardware as connected when shipped. A copy of this program to be
included on the software CD to allow the user to re-instate it if
desired after overwriting it. Suggested experiments listed in
following sub paragraphs.
4.3.1 Digital bar graph steps through bars, one bar at a time, or
in "thermometer mode" to allow user to observe use of virtual
I/O monitoring. Step rate variable to allow effect of I/O
being faster than virtual I/O sample rate.
4.3.2 Use 7 segment display as counter. Count could be controlled by
rotary encoder, or by internal timer. Again count rate
variable to see effects on virtual monitor.
4.3.3 Use 7 segment display as clock. Use push buttons or virtual
I/O for setting time and/or alarm. Again an exercise in
virtual monitoring.
4.3.4 Use 7 segment display as voltmeter readout to read voltage
from potentiometer and/or virtual analogue source on iPIC.
Exercise in using virtual analogue monitor on iPIC as well.
4.3.5 Use temperature sensor chip as analogue source for voltmeter
operation. Other wise very similar to 4.3.4.
4.3.6 Use "virtual comms port" on programming lines to get target
processor to relay message out serial port from typing coming
in through iPIC from host PC.
5. Target 2 Processor.
5.1 A socket is provided to take a 40 pin DIP chip of identical
specification to any that can be fitted to target 1. No chip is
supplied in the "as shipped" board. The chip fitted to this socket
does not have to be identical to the chip in Target 1, it can be
any chip from the allowable family.
5.2 The only dedicated hardware provided for this target is a jumper to
allow the uart to be connected to the serial port. Leaving the
jumper off allows the uart pins to be used as general I/O.
5.3 Connection pins are provided to allow any hardware peripheral on
the board to be jumpered to this target using flying leads. No
assumptions are made about pin usage other than possible uart use
as given in 5.2.
6. Target 3 ICSP port.
6.1 A connector is to be provided to allow a PIC on an external PCB to
be programmed using the on board hardware. It is yet to be decided
if this should use an RJ11 connector in the same manner as the
Microchip ICD.
6.2 The programming hardware is to be capable of using this port for
debugging use in the same manner as the Microchip ICD.
6.3 No cable will be provided with the kit for this port.
7. PCB hardware.
7.1 The iPIC is to be soldered in circuit. My preference is to use a
surface mount chip. If this is an 18F452, then this will have no
impact on ordering as it will be a different processor to that
supplied for target 1. I am not unmovable on this, the final
decision resting with those who assemble the hardware.
7.2 The Target 1 and Target 2 processor sockets should have enough room
around them on the PCB to use ZIF sockets if the price for these is
suitable.
7.3 All components as far as possible should be surface mount. Again I
am not unmoveable on this, but believe it would probably be easier
for production machinery. Again the hardware manufacturer to have
final say on this.
7.4 My favoured size for the PCB is 100mm x 160mm (Eurocard size), but
to get a reasonable breadboard area may need to go to 100mm x 220mm
(extended Eurocard) or 200mm x 160mm (double height Eurocard). Again
I am not inflexible on this, but see it as a size that many in our
business would use as the basis of developing prototypes.
8. Host PC Software.
8.1 Host software will need to be written to handle various functions
as listed in the sub paragraphs below.
8.1.1 Download and control programming of target device from host.
This includes selection of the target processor to be
programmed.
8.1.2 Control and display of virtual I/O information. This includes
remote reset of the target processors.
8.1.3 Conversion of virtual I/O data into human readable display on
screen to form a virtual peripheral (e.g. converting port bit
information into LCD display). This may also require setting
which port pins, and in which order are to form the input
to the virtual peripheral.
8.1.4 Allow up to two "dumb terminals" as separate windows within
the host program to handle I/O from either serial ports, or
"virtual serial I/O" handled through the iPIC as mentioned
in 3.10. "Serial Ports" should include USB comms ports as
an option.
8.1.5 Control the ICD functions in the iPIC to allow the user to
debug programs.
8.2 Any virtual peripheral suitable for use in paragraph 8.1.3 should
probably be written as a DLL (or *nix equivalent) to maximise the
portability of code. A defined interface for writing such DLL code
will need to be written to facilitate this.
8.3 The software should be written in a language that allows best
portability to the widest range of systems practicable, with a
minimum of effort. To me this means that an environment which
allows programming isolation of display handling from coding
requirements would be best. Use of Delphi/Kylix or a multi-platform
C/C++ would seem to be the most sensible way. A *nix port can
probably be ported to a Mac OS environment with minimum extra
effort due to it's *nix basis.
8.4 A suite of assembler, linker, and debugger functions which link to
the source code will need to be provided. Thought will also be
needed in what to provide as an editor.
9. Chip selection to use on the PCB.
9.1 This is my selection of hardware to use on the target PCB. It is
not set in stone, just what I have figured would be useful items
to use.
9.2 Bar graph display. There are a wide range of these available in
0.3" DIP packages. I am not aware of any surface mount versions,
but pointers to low profile ones may be nice.
9.3 Seven segment display. There are two possibilities I like. The first
is an Agilent one, which appears to be a new device that the Agilent
search engine cannot find on their site, but is listed in the seven
segment display list. Agilent #HDSM-560G, 0.39" 4 digit green
display. The first digit is actually a starburst allowing +, -, /
etc, and it also has a colon between the two centre digits as well
as a decimal point for each digit. Cost unknown.
The second is a Kingbright LC-305MK, stocked by RS Components, but
no longer on the Kingbright web site. This means it is probably a
"Not for New Design" type device. Five digit 7 segment with DP for
all digits, plus DP's at the top of each side of the centre digit,
allowing a (wide spaced) colon for clock use, or two DP for inverted
use.
9.4 Analogue input device, my suggestion being a temperature sensor such
as an LM35, to represent a potential "real world" sensor that the
user can experiment with. LM35 comes from National Semiconductor,
but other chips with voltage output are available.
9.5 Analogue output device, my suggestion is an LM3919 bar graph display
driver. This can be jumpered to show a single bar or "thermometer"
type display. Useful for displaying filtered PWM output.
9.6 High current driver, ULN2803A, surface mount version, available from
Toshiba and Allegro. Eight drivers in one package, for driving 7
segment display and digital bar graph, also used for miscellaneous
drivers like programming high voltage switch, and virtual reset
buttons. Useful as it has internal resistors in series with the base
to limit current, and base to ground to put into known state if user
leaves unconnected. Being bipolar, not damaged if input O/C.
9.7 Op-amps to buffer/protect analogue i/o. Suggest National
Semiconductor LMC6482/4 which is a dual/quad rail to rail I/O
device. Works down to 3V, so ideal to run off 5V processor supply.
Actual device used depends on how many individual op-amps we
require.
9.8 Virtual Output - because of the number of I/O lines we would be
wanting to monitor, I believe we would need to use a shift register
to get them all into the iPIC to transfer to the host. I suggest
using a 74HC573 or 74HC574 8 bit latch/shift register for this,
depending on wether an edge latched or fall through latch is
perceived as more desirable. These would require an extra line on
the iPIC to drive the latch function, but with all bits latched at
once, it would provide a "window" on the state of the processors. I
count 33 I/O lines, plus reset to monitor, so 9 shift registers
would monitor both processors, and have a handful of pins left over
that the user can connect elsewhere using floating leads.
9.9 Virtual Input - I am looking to use a pair of 74HC595 SIPO 8 bit
registers to give 16 output lines that can be connected to processor
pins on either processor using flying leads. A small (100 ohm?)
resistor would need to be connected in series with each output to
protect things if connected to a PIC pin configured as an output.
Like the HC573/4, these would need another separate pin to drive the
latch line.
9.10 Pull up/down resistors. Suitable resistor packs to be sourced. Not
sure if I should just go with SIP through hole packs or find SMD
packs.
Well that will do for today - i will come back in the morning to a wealth of
discussion points I'm sure. I believe my spell checker caught most of the
errors, but don't count on it :)
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2002\09\05@132634
by
Byron A Jeff
[Deleted for brevity]
One word: WOW!!!
Any points that I have are so nitpicky I'm not going to even bother.
When can I get one?
BAJ
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2002\09\05@133052
by
Dominic Stratten
Well it makes a change for me to agree about something but I think that
Alans got a lot of this right. I've snipped out all the bits I agree on and
commented on the things I disagree on.
{Original Message removed}
2002\09\05@140924
by
Wouter van Ooijen
> This is my general discussion document for where I see the
> PIC Beginners Kit heading as a project.
I would prefer to call it a set or something, because a kit sounds like
'solder it yourself'.
Estimated price?
Wouter van Ooijen
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2002\09\05@143038
by
Byron A Jeff
On Thu, Sep 05, 2002 at 06:33:21PM +0100, Dominic Stratten wrote:
OK. I guess I can now be nitpicky ;-)
> Well it makes a change for me to agree about something but I think that
> Alans got a lot of this right. I've snipped out all the bits I agree on and
> commented on the things I disagree on.
>
> {Original Message removed}
2002\09\05@143707
by
Byron A Jeff
On Thu, Sep 05, 2002 at 08:07:22PM +0200, Wouter van Ooijen wrote:
> > This is my general discussion document for where I see the
> > PIC Beginners Kit heading as a project.
>
> I would prefer to call it a set or something, because a kit sounds like
> 'solder it yourself'.
More nitpicking: I'd like to see the beginner dropped too. Of course I'm still
partial to the name I choose several week ago: The PICLIST Designer.
>
> Estimated price?
No clue. Sean said it wasn't even possible to discuss until consensus on
design has been reached. We're close.
I know that you and I have had discussions about price. I know that you feel
that the cheaper it is, the better off we are. I agree up to the point where
we start to lose product effacacy.
We shall see I guess.
BAJ
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2002\09\05@155229
by
Quentin
2002\09\06@045448
by
Alan B. Pearce
OK, I'll reply in the order I received the mails, although where there are
multiple comments on a point, I have intermingled them.
>When can I get one?
Well It is going to be a while, by the time I fit the circuit design into
spare time at my Orcad machine :)
Sorry, but I would like a couple yesterday too :))
>> 1.9.3 LM3919 type bargraph for analogue voltage display
>I dont think this it totally necessary - ....
Well I was wanting something that had a certain amount of WOW factor for a
beginner, and this seemed to be a sensible way to go without having a full
DVM. However as I said in the next paragraph, one of the "built in"
experiments as supplied is a DVM using the ADC in the target to drive the
seven segment display. Yes there is some duplication by doing this, so I may
rethink this. Perhaps having the tracking there, but not fitting the
components :)
>> 2.11 Breadboard area to be provided using "measles array" of solder pads
>> on 0.1" centres. Area to cover all otherwise unused space on PCB.
>Eeeeeeeuch - let the hobbyist loose on the board with a soldering iron
??? -
>Much as people hate them, I think that an optional (pick a standard sized
>one and leave space for it) Breadboard would be a better idea here - ....
Yes I agree, but the hobbyist I think will do most of their experimenting by
programming, and using existing hardware or virtual peripherals. If a
suitable breadboard can be persuaded to fit, then so much the better.
However for developers who use the board, then the solder area is probably
better :) For this reason I would be tempted to have the breadboard easily
removable if supplied fitted, which it would need to be if we are to avoid
having the hobbyist do soldering :{}
>Woooohoooo - I love Zif sockets. They do plug into a standard 40pin dip
>header though so it might be an idea to have Target 1 and Target 2 sockets
Well Sean reckoned he could get ZIF sockets at real good prices in Taiwan,
so I was reckoning on fitting these straight off. Low profile ones
preferred.
>Just my 2 cents worth but this was well worth the effort Alan. I feel
>you've covered most of the requirements - its just down to cost now.
Thanks for the complement. It is going to take a while to get to the point
of costing it though.
Wouter said
>I would prefer to call it a set or something, because a kit
>sounds like 'solder it yourself'.
Byron said
>I'd like to see the beginner dropped too. Of course I'm still
>partial to the name I choose several week ago: The PICLIST Designer.
Agreed, and I think I do prefer the name Byron has come up with, which is
also possibly more likely to get a hobbyist to purchase it ironically :)
>Estimated price?
No estimate yet, I will carry on doing a circuit, and come up with a list of
parts, that people can work with. I would like to get some test PCB's done
fairly early on, possibly through Tsvetsan, and if that is done then people
can get them from him and build test version, and come up with software
modules for it.
>Suggestion: How about making Target 2 a 28 pin? This is the other
>favourite "footprint". Then you have the best of both worlds.
Well my attitude on this is that if a developer is designing for a 28 pin
destination chip, then while using the Piclist Designer, they use a 40 pin
chip, using only the resources that are in the 28 pin chip. I have not gone
digging in the data sheets to see if the pinouts allow easy conversion
between the two footprints. Bear in mind that I am expecting to have a
jumper selected crystal and RC osc components for target 2. There were a
number of bits like this and the USB chip which got forgotten in the brief.
>Also, is there allowance for I2C? Good for training and further expansion.
I have not made specific allowance as such for I2C, but there is no reason
why the I2C hardware in either (or both) of the target processors cannot be
used. All I/O pins will be potentially available to do whatever the user
requires. As I said in the brief, the only pins vaguely allocated on Target
2 are the uart pins. I2C can be built up on the breadboard area.
OK, I will carry on working on a circuit for now, and see what I come up
with.
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2002\09\06@053352
by
Alan B. Pearce
>> 1.9.3 LM3919 type bargraph for analogue voltage display
>I dont think this it totally necessary - ....
Well it looks like this is going to be a non-starter, as it seems no-body
makes it anymore. So that kills off that hardware.
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2002\09\06@065723
by
Russell McMahon
>>> 1.9.3 LM3919 type bargraph for analogue voltage display
> >I dont think this it totally necessary - ....
> Well it looks like this is going to be a non-starter, as it seems no-body
> makes it anymore. So that kills off that hardware.
Use a PIC :-)
12Cxx even with Scott's Sigma Delta converter.
One cap, few R's, RC Osc.
LED driver R's a nuisance. Maybe PWM straight to LEDs with no resistors
(blasphemy :-) ).
Possibly even cheaper than original 3919!
RM
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2002\09\06@095216
by
Sean Alcorn (SYD)
|
Alan,
> 9.2 Bar graph display. There are a wide range of these available in
> 0.3" DIP packages. I am not aware of any surface mount versions,
> but pointers to low profile ones may be nice.
There are a plethora of these available in Taiwan. We should be able to find
something suitable.
{Quote hidden}> 9.3 Seven segment display. There are two possibilities I like. The first
> is an Agilent one, which appears to be a new device that the Agilent
> search engine cannot find on their site, but is listed in the seven
> segment display list. Agilent #HDSM-560G, 0.39" 4 digit green
> display. The first digit is actually a starburst allowing +, -, /
> etc, and it also has a colon between the two centre digits as well
> as a decimal point for each digit. Cost unknown.
> The second is a Kingbright LC-305MK, stocked by RS Components, but
> no longer on the Kingbright web site. This means it is probably a
> "Not for New Design" type device. Five digit 7 segment with DP for
> all digits, plus DP's at the top of each side of the centre digit,
> allowing a (wide spaced) colon for clock use, or two DP for inverted
> use.
Here you need to leave this to us. I will send you a PDF file of the "Garden
Variety" available in Taiwan. Nice and cheap and if one supplier lets us
down, we can get the same device from a dozen others.
Will we want Common Anode or Common Cathode?
Cheers,
Sean
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2002\09\06@100550
by
Alan B. Pearce
>Here you need to leave this to us. I will send you a PDF file of
>the "Garden Variety" available in Taiwan. Nice and cheap and if
>one supplier lets us down, we can get the same device from a
>dozen others.
I figured that would probably be the case. The Agilent one I mentioned just
looked like a real nice device for what I envisaged.
>Will we want Common Anode or Common Cathode?
Well I think common anode would be the best, this means we can use a
2003/2803 to drive the cathodes, and level shift to the digit select
transistor.
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2002\09\06@125225
by
Dwayne Reid
At 10:33 AM 9/6/02 +0100, Alan B. Pearce wrote:
> >> 1.9.3 LM3919 type bargraph for analogue voltage display
>
> >I dont think this it totally necessary - ....
Wrong part number: look for LM3914. There are also LM3915 & 3916 but those
are intended for audio use (3 dB steps or VU response respectively).
dwayne
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2002\09\06@131336
by
Roman Black
|
|
Sean Alcorn (SYD) wrote:
> > 9.3 Seven segment display. There are two possibilities I like. The first
> > is 4 digit green
> > display.
> > or Five digit 7 segment with DP for
> > all digits, plus DP's at the top of each side of the centre digit,
> > allowing a (wide spaced) colon for clock use, or two DP for inverted
> > use.
>
> Here you need to leave this to us. I will send you a PDF file of the "Garden
> Variety" available in Taiwan. Nice and cheap and if one supplier lets us
> down, we can get the same device from a dozen others.
Hi Sean, what is the price differential between
the multi-digit 7-seg displays and a Taiwanese
LCD, say a cheap 20x2 or something??
The ideal of a "designer" product is to design
things on, and a great deal more future projects
can be done with LCD and alpha characters, ie
text menu systems etc.
If it only bumps the cost of the thing a couple
of percent in selling price, the LCD is worth
considering. :o)
-Roman
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2002\09\07@034527
by
Sean Alcorn (SYD)
Hi Roman,
> Hi Sean, what is the price differential between
> the multi-digit 7-seg displays and a Taiwanese
> LCD, say a cheap 20x2 or something??
Actually, a 0.3" 4 digit 'Clock Display' is approaching a couple of bucks.
Just before I started this discussion, I found a really nice 20x2 LCD module
for about $7
> If it only bumps the cost of the thing a couple
> of percent in selling price, the LCD is worth
> considering. :o)
Why couldn't we have both? A plug in LCD module or our own LED module that
shared the connectors?
I personally would use the LED far more than the LCD, but I realise others
would be the other way.
Regards,
Sean
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2002\09\07@060749
by
2002\09\07@065336
by
Sean Alcorn (SYD)
Hi Jan-erik,
> As a newcommer to the piclist mailinglist, is there
> a summary description of the PKB somewhere ?
> Maybe on the www ?
No. Not yet. It's only really just starting to take shape. I am thinking
about setting up a web site on Monday.
Regards,
Sean
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2002\09\07@091907
by
Roman Black
|
|
Sean Alcorn (SYD) wrote:
> Actually, a 0.3" 4 digit 'Clock Display' is approaching a couple of bucks.
> Just before I started this discussion, I found a really nice 20x2 LCD module
> for about $7
Ok, for the extra $5 or so it would have to be
a must in the "ultimate piclist designer"?? :o)
> > If it only bumps the cost of the thing a couple
> > of percent in selling price, the LCD is worth
> > considering. :o)
>
> Why couldn't we have both? A plug in LCD module or our own LED module that
> shared the connectors?
Here's the problem. It's no longer $5 or 7$ for
the LCD to be included in the product. It is now
$7 + another $5 for the plug in board and connectors
etc. + Extra costs for manufacturing two boards when
only one is needed. + Extra hassle dealing with
orders and customers, where some want module B
but others want module A only, and what manufacturing
quantities of each module etc do you make? And expect
people to stock? Part numbers? Distribution? Prices?
I'm really convinced that a *complete* system is best
for everyone, ie one board with everything on it.
One simple price, no arguments. Remember we are the
people who will need to tell 500 beginners why they
need module B or answer their extra questions about
which modules they need when they are totally ignorant
about the modules AND their needs. I remember the
original points about the PBK included the "common
starter kit for beginners" "one set of answers for
everyone" logic which is one of its strengths. Surely
we don't want to be constantly answering questions of
"which modules do I need" asked by people that don't
yet know what they need it to do?? Piclist hell.
In the interest of actually using it to design useful
future projects we would have to consider having an
LCD, and menu buttons, ie up/down forw/back. Isn't this
going to use the larger PICs? I think a designer board
useful for designing larger PIC projects must have the
ability to have a standard text menu system that users
expect these days.
On the other hand, if the Piclist designer is only
aimed at programming 16F84's and flashing leds there
are many GREAT products already out there?? ;o)
-Roman
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2002\09\07@222031
by
Gwynne Reddick
2002\09\07@232407
by
Scott Dattalo
On Sun, 8 Sep 2002, Gwynne Reddick wrote:
> On Sat, 7 Sep 2002 20:52:35 +1000, Sean Alcorn (SYD) wrote:
>
> >No. Not yet. It's only really just starting to take shape. I am
> >thinking about setting up a web site on Monday.
> >
> >Regards,
> >
> >Sean
>
> I can provide free hosting, if it's needed.
And my offer still stands:
http://www.gnupic.org/pbk.html
Scott
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2002\09\08@150017
by
Gwynne Reddick
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