MPJA LCD Display Adapter
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Finally got a response from Marlin P Jones -- turns out the freebie 1 x 16
LCD is treated as a 2 x 8 display. Go figure.
Anyhow, I had a spare BS1 module and a Basic Stamp Activity Board, so I
threw it all together and got the display working briefly. However, its back
to displaying Smile again, so at this point I don't have a clue. Looks like
it may be some sort of timing issue as the display resets OK but translates
the first characters wrong. From there its downhill.
LCD is treated as a 2 x 8 display. Go figure.
Anyhow, I had a spare BS1 module and a Basic Stamp Activity Board, so I
threw it all together and got the display working briefly. However, its back
to displaying Smile again, so at this point I don't have a clue. Looks like
it may be some sort of timing issue as the display resets OK but translates
the first characters wrong. From there its downhill.
Comments
to accept data. You also need to allow a small amount of time (25ms)
after you configure the LCD for 4-bit, 8-bit, etc. Whenever I use an
LCD with the BS2, I put a pause 1000 statement as the very first line
(or right before I need to use the LCD). The datasheet for the
HD44780 gives the exact times.
Those 1x16 displays are a real pain because they are setup as a 2x8.
If you want some high quality, inexpensive LCDs, check out
http://www.eio.com. They have 2x16 LED BACKLIT LCD's for $10 each.
They have one with cables and a plug for the LED power already
installed. Check out: http://www.eio.com/lcdprodt.htm. They have free
shipping if you pay with PayPal.
Good luck,
--Jeff Wallace
*Add a RTC, 256k EEPROM, 8 extra I/O, and an 8 channel ADC to the BS2
http://www.high-techgarage.com/products/supermax.php
--- In basicstamps@y..., Rodent <daweasel@s...> wrote:
> Finally got a response from Marlin P Jones -- turns out the freebie
> 1 x 16 LCD is treated as a 2 x 8 display. Go figure. Anyhow, I had
> a spare BS1 module and a Basic Stamp Activity Board, so I threw it
> all together and got the display working briefly. However, its back
> to displaying Smile again, so at this point I don't have a clue.
> Looks like it may be some sort of timing issue as the display
> resets OK but translates the first characters wrong. From there its
> downhill.
serial display, and this deal sounded like the plan. I've got access to all
sorts of exotic parallel displays, but I would still have to use a converter
or buy a serial display.
Original Message
> Most LCD's can take up to 1 second before their electronics are ready
> to accept data. You also need to allow a small amount of time (25ms)
> after you configure the LCD for 4-bit, 8-bit, etc. Whenever I use an
> LCD with the BS2, I put a pause 1000 statement as the very first line
> (or right before I need to use the LCD). The datasheet for the
> HD44780 gives the exact times.
>
> Those 1x16 displays are a real pain because they are setup as a 2x8.
> If you want some high quality, inexpensive LCDs, check out
> http://www.eio.com. They have 2x16 LED BACKLIT LCD's for $10 each.
> They have one with cables and a plug for the LED power already
> installed. Check out: http://www.eio.com/lcdprodt.htm. They have free
> shipping if you pay with PayPal.
>
> > Finally got a response from Marlin P Jones -- turns out the freebie
> > 1 x 16 LCD is treated as a 2 x 8 display. Go figure. Anyhow, I had
> > a spare BS1 module and a Basic Stamp Activity Board, so I threw it
> > all together and got the display working briefly. However, its back
> > to displaying Smile again, so at this point I don't have a clue.
> > Looks like it may be some sort of timing issue as the display
> > resets OK but translates the first characters wrong. From there its
> > downhill.
as planned, sometimes it displays Smile. It worked several times with normal
serial output, and several times with inverted output. Looks to me like
someone didn't work out all the bugs. I may write Wirz directly and see what
they have to say.
We played a bit further and figured out their display adapter sometimes
interprets the stamp pin going high after reset as a character, which hoses
up everything. It may work out better to fire up the stamp, get the pin
high, then turn on the LCD -- that way the data line is high when the
display adapter finishes its setup.
Original Message
> Most LCD's can take up to 1 second before their electronics are ready
> to accept data. You also need to allow a small amount of time (25ms)
> after you configure the LCD for 4-bit, 8-bit, etc. Whenever I use an
> LCD with the BS2, I put a pause 1000 statement as the very first line
> (or right before I need to use the LCD). The datasheet for the
> HD44780 gives the exact times.