BS2 to EDE702 to LCD, Problem with LCD
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I am having problems with my LCD,
I am new to this and I got an LCD, I am trying to hook it up to my BS2, it is not serial, I got it from DIGI-KEY and the vendor is Varatronics and the only numbers I see on·the PCB are 16265 R3, but from looking around I assume most LCD's have the same pin info. on the back there are 2 micro's with stickers over them, one is the HD44100FS, and the·other is HD44780A00
The LCD I have is 16x2 and its backlit. its 16 pins, the first two being the backlight, so 14 pins.
when the power is enabled alls I get is the first line full of boxes?, I haven't seen it do much else, I bought a EDE702 Serial interface and still no difference, thought it would make it less confusing to figure out what was wrong. its nice to only have 3 wire interface as·opposed to·regular way.
The EDE702 is working I can turn an LED on and off via the digital output on the EDE702 so I know the chip works with my serout command , but no change on the LCD.. I have been trying to figure it out. driving me nuts
is there an easy way to know if the LCD works? like a test or something?
can anyone help me out!
Thanks in advance
Tyson
tysonstephen@home.com
I am new to this and I got an LCD, I am trying to hook it up to my BS2, it is not serial, I got it from DIGI-KEY and the vendor is Varatronics and the only numbers I see on·the PCB are 16265 R3, but from looking around I assume most LCD's have the same pin info. on the back there are 2 micro's with stickers over them, one is the HD44100FS, and the·other is HD44780A00
The LCD I have is 16x2 and its backlit. its 16 pins, the first two being the backlight, so 14 pins.
when the power is enabled alls I get is the first line full of boxes?, I haven't seen it do much else, I bought a EDE702 Serial interface and still no difference, thought it would make it less confusing to figure out what was wrong. its nice to only have 3 wire interface as·opposed to·regular way.
The EDE702 is working I can turn an LED on and off via the digital output on the EDE702 so I know the chip works with my serout command , but no change on the LCD.. I have been trying to figure it out. driving me nuts
is there an easy way to know if the LCD works? like a test or something?
can anyone help me out!
Thanks in advance
Tyson
tysonstephen@home.com
Comments
there are still
boxes on line one then hook pin 4 to ground all should be fine
> Tyson Stephen wrote:
>
> I am having problems with my LCD,
>
> I am new to this and I got an LCD, I am trying to hook it up to my BS2, it is
not serial,
> I got it from DIGI-KEY and the vendor is Varatronics and the only numbers I
see on the PCB
> are 16265 R3, but from looking around I assume most LCD's have the same pin
info. on the
> back there are 2 micro's with stickers over them, one is the HD44100FS, and
the other is
> HD44780A00
>
> The LCD I have is 16x2 and its backlit. its 16 pins, the first two being the
backlight, so
> 14 pins.
> when the power is enabled alls I get is the first line full of boxes?, I
haven't seen it
> do much else, I bought a EDE702 Serial interface and still no difference,
thought it would
> make it less confusing to figure out what was wrong. its nice to only have 3
wire
> interface as opposed to regular way.
>
> The EDE702 is working I can turn an LED on and off via the digital output on
the EDE702 so
> I know the chip works with my serout command , but no change on the LCD.. I
have been
> trying to figure it out. driving me nuts
>
> is there an easy way to know if the LCD works? like a test or something?
>
> can anyone help me out!
>
> Thanks in advance
>
> Tyson
> tysonstephen@h...
>
\
> eGroups.com Home: http://www.egroups.com/group/basicstamps
> www.egroups.com - Simplifying group communications
Original Message
From: LarryGaminde <lgaminde@t...>
To: <basicstamps@egroups.com>
Sent: Monday, March 27, 2000 1:54 PM
Subject: [noparse][[/noparse]basicstamps] Re: BS2 to EDE702 to LCD, Problem with LCD
> I think the backlight should be 15,16 and if you have it hooked up right
and there are still
> boxes on line one then hook pin 4 to ground all should be fine
>
well the backlight is the two pins before pin 1, pin 1 is marked. and I
don't have any probs lighting the back. but I just can't get this thing to
work. I have tried grounding pin 4 which is the RS and I still have a first
line full of black boxes.
> > Tyson Stephen wrote:
> >
> > I am having problems with my LCD,
> >
> > I am new to this and I got an LCD, I am trying to hook it up to my BS2,
it is not serial,
> > I got it from DIGI-KEY and the vendor is Varatronics and the only
numbers I see on the PCB
> > are 16265 R3, but from looking around I assume most LCD's have the same
pin info. on the
> > back there are 2 micro's with stickers over them, one is the HD44100FS,
and the other is
> > HD44780A00
> >
> > The LCD I have is 16x2 and its backlit. its 16 pins, the first two being
the backlight, so
> > 14 pins.
> > when the power is enabled alls I get is the first line full of boxes?, I
haven't seen it
> > do much else, I bought a EDE702 Serial interface and still no
difference, thought it would
> > make it less confusing to figure out what was wrong. its nice to only
have 3 wire
> > interface as opposed to regular way.
> >
> > The EDE702 is working I can turn an LED on and off via the digital
output on the EDE702 so
> > I know the chip works with my serout command , but no change on the
LCD.. I have been
> > trying to figure it out. driving me nuts
> >
> > is there an easy way to know if the LCD works? like a test or something?
> >
> > can anyone help me out!
> >
> > Thanks in advance
> >
> > Tyson
> > tysonstephen@h...
>
>
> > eGroups.com Home: http://www.egroups.com/group/basicstamps
> > www.egroups.com - Simplifying group communications
>
>
> -- Check out your group's private Chat room
> -- http://www.egroups.com/ChatPage?listName=basicstamps&m=1
>
>
>
>well the backlight is the two pins before pin 1, pin 1 is marked. and I
>don't have any probs lighting the back. but I just can't get this thing to
>work. I have tried grounding pin 4 which is the RS and I still have a first
>line full of black boxes.
The RS pin needs to be connected to the EDE chip, not to ground.
Doublecheck your wiring, with me it's always the wiring. The line of boxes
means the LCD is being powered up without the controller being initialized.
You have to tell_the_controller that it's a two line display. I have some
control codes (and other LCD links) on my page at:
http://www3.sympatico.ca/orthner/serialcd.html
Cheers, Duncan
Original Message
From: <orthner@s...>
To: <basicstamps@egroups.com>
Sent: Monday, March 27, 2000 2:33 PM
Subject: [noparse][[/noparse]basicstamps] Re: BS2 to EDE702 to LCD, Problem with LCD
> At 02:02 PM 3/27/00 -0800, you wrote:
> >
> >well the backlight is the two pins before pin 1, pin 1 is marked. and I
> >don't have any probs lighting the back. but I just can't get this thing
to
> >work. I have tried grounding pin 4 which is the RS and I still have a
first
> >line full of black boxes.
>
> The RS pin needs to be connected to the EDE chip, not to ground.
> Doublecheck your wiring, with me it's always the wiring. The line of boxes
> means the LCD is being powered up without the controller being
initialized.
> You have to tell_the_controller that it's a two line display. I have some
> control codes (and other LCD links) on my page at:
>
> http://www3.sympatico.ca/orthner/serialcd.html
>
> Cheers, Duncan
>
>
Well I am still having problems so I will give you all a general Idea of
what the circuit looks like
I have pin 1, 2, 3, 4 of the EDE all to 5V, pin1 is the baud 2400=0,9600=1,
and pin 2 is the polarity, 0=inverted, 1=standard. and pin 3 and pin 4 are 5
volts
pin 5 is connected to ground
pin 6 is connected to the enable pin 6 on the LCD
pin 7 is the RS pin 4 on the LCD
pin 8 is the RW pin 5 on the LCD
pin 9 NA
pin 10 is connected to DB4 on the LCD pin 11
pin 11 is connected to DB5 on the LCD pin 12
pin 12 is connected to DB6 on the LCd pin 13
pin 13 is connected to DB7 on the LCD pin 14
pin 14 is connected to 5v which is connected to the LCD pin 2
pin 15 and 16 are connected together with a 4mhz resonator
pin 17 is the data line connected to pin 7 on the basic stamp 2
pin 18 is the digital out, which I have an LED connected to, which works
when I send the command
serout 7, n9600,[noparse][[/noparse]$FE]
serout 7, n9600,[noparse][[/noparse]%11111100] to turn the LED on and [noparse][[/noparse]%11111101 to turn it on.
pin 1 on the LCD is connected to ground, pin 2 is connected to 5v and pin 3
is connected to the POT.
ok my basic stamp 2 code sorta goes like this
N9600 con 84 ' Variable defination and 84 is what I got from the basic stamp
manual for 9600 baud non inverted.
lcd con 7 ' definition that the LCD data line is pin7
loop:
pause 200 ' to let the LCD initialize, never initializes though
serout 7, n9600,[noparse][[/noparse]$FE]
serout 7, n9600,[noparse][[/noparse]%000011]
pause 10
serout 7, n9600,[noparse][[/noparse]$FE]
serout 7, n9600,[noparse][[/noparse]%000011]
pause 10
serout 7, n9600,[noparse][[/noparse]$FE]
serout 7, n9600,[noparse][[/noparse]%000011]
pause 10
serout 7, n9600,[noparse][[/noparse]$FE]
serout 7, n9600,[noparse][[/noparse]%000010]
pause 10
serout 7, n9600,[noparse][[/noparse]$FE]
serout 7, n9600,[noparse][[/noparse]%000010]
serout 7, n9600,[noparse][[/noparse]%001010]
pause 10
serout 7, n9600,[noparse][[/noparse]$FE]
serout 7, n9600,[noparse][[/noparse]%001000]
pause 10
serout 7, n9600,[noparse][[/noparse]$FE]
serout 7, n9600,[noparse][[/noparse]%000001]
pause 10
serout 7, n9600,[noparse][[/noparse]$FE]
serout 7, n9600,[noparse][[/noparse]%000110]
pause 10
serout 7, n9600,[noparse][[/noparse]$FE]
serout 7, n9600,[noparse][[/noparse]$01]
pause 10
pause 10
serout LCD,N9600,[noparse][[/noparse]"Hello LCD"] 'Supposed to print this on LCD'
serout 7,n9600,[noparse][[/noparse]$FE] '=254 blank space?
serout 7,n9600,[noparse][[/noparse]$C0] '=goes to second line
pause 10
serout 7,n9600,[noparse][[/noparse]"This should be the second line"]
This is where I got the info for initializing any HD44780 Controlled LCD
When interface is 4-bits wide
[noparse][[/noparse]Power ON]
[noparse][[/noparse] Wait more than 15ms ]
[noparse][[/noparse]after Vdd rises to 4.5v]
RS R/W DB7 DB6 DB5 DB4 Can't check BF before this instruction
0 0 0 0 1 1 Function set (8-bit interface)
[noparse][[/noparse]Wait more than]
[noparse][[/noparse] 4.1ms ]
RS R/W DB7 DB6 DB5 DB4 Can't check BF before this instruction
0 0 0 0 1 1 Function set (8-bit interface)
[noparse][[/noparse]Wait more than]
[noparse][[/noparse] 100us ]
RS R/W DB7 DB6 DB5 DB4 Can't check BF before this instruction
0 0 0 0 1 1 Function set (8-bit interface)
BF can be checked after the following
instructions. When BF is not checked,
the waiting time between instructions
is longer than the execution time.
(See Instruction set)
RS R/W DB7 DB6 DB5 DB4
0 0 0 0 1 0 Function set (to 4-bit interface)
RS R/W DB7 DB6 DB5 DB4
0 0 0 0 1 0
0 0 N F * * Function set [noparse][[/noparse]4-bit Interface ]
[noparse][[/noparse]Specify display lines]
RS R/W DB7 DB6 DB5 DB4 [noparse][[/noparse]and character font ]
0 0 0 0 0 0 These cannot be
0 0 1 0 0 0 Display OFF changed afterwards
RS R/W DB7 DB6 DB5 DB4
0 0 0 0 0 0
0 0 0 0 0 1 Display ON
RS R/W DB7 DB6 DB5 DB4
0 0 0 0 0 0
0 0 0 1 I/D S entry mode set
I am not sure I put this in my code correctly, since nothing works I have
tried numerous combinations.
if this is not clear email me and I will try to explain better....
Your hardware connection looks good, and the fact that the EDE702 is
receiving serial data and toggling the LED means that quite a few things are
correct. Since you can see the top row of segments on, it sounds as if your
contrast is O.K. but that the LCD is never being initialized. I noticed
that you had code for initializing the LCD; this shouldn't be necessary, as
the EDE702 handles all of this at powerup; you should only need to connect
the EDE702 to the LCD, power it up, and all segments will be blank with the
display initialized. You can write text without any further initialization
on your part.
Is the LCD module connector a 1x14 or 2x7 connector? Sometimes it's easy to
miswire those 2x7 connectors and mistake the pin count. Also, I've seen a
lot of connections from the EDE702 to the lower nibble of the LCD module; it
needs to be to the upper. Doublecheck that as well. If you're still stuck,
give me a call at (816) 257-9954 and we'll walk through the circuit pin by
pin.
Good luck,
Todd Peterson
E-Lab Digital Engineering, Inc.
--Manufacturers of the EDExx IC Family--
(816) 257-9954 FAX: (816) 257-9945
http://www.elabinc.com
Original Message
From: Todd Peterson <toddp@e...>
To: <basicstamps@egroups.com>
Sent: Tuesday, March 28, 2000 8:32 AM
Subject: [noparse][[/noparse]basicstamps] Re: BS2 to EDE702 to LCD, Problem with LCD
> > pin 18 is the digital out, which I have an LED connected to, which works
>
> Your hardware connection looks good, and the fact that the EDE702 is
> receiving serial data and toggling the LED means that quite a few things
are
> correct. Since you can see the top row of segments on, it sounds as if
your
> contrast is O.K. but that the LCD is never being initialized. I noticed
> that you had code for initializing the LCD; this shouldn't be necessary,
as
> the EDE702 handles all of this at powerup; you should only need to connect
> the EDE702 to the LCD, power it up, and all segments will be blank with
the
> display initialized. You can write text without any further
initialization
> on your part.
>
> Is the LCD module connector a 1x14 or 2x7 connector? Sometimes it's easy
to
> miswire those 2x7 connectors and mistake the pin count. Also, I've seen a
> lot of connections from the EDE702 to the lower nibble of the LCD module;
it
> needs to be to the upper. Doublecheck that as well. If you're still
stuck,
> give me a call at (816) 257-9954 and we'll walk through the circuit pin by
> pin.
>
Yah I knew that the ede702 did all the initializing, but when it didn't work
I just was trying everything... [noparse]:)[/noparse]..
its a 1-16 pin configuration so
The vss is labeled pin 1
0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0
db7 db6 db5 db4 db3 db2 db1 db0 E RW RS
VEE VDD VSS + - for the back light
Pardon my knwoledge gap, but what exactly do you mean be the lower nibble of
the LCD? I think i have heard a few things like this but don't know what it
means.
Thanks a bunch I am learning a lot from this problem.
-Tyson