Repair or replace 4x20 serial LCD?
M. Kibat
Posts: 12
Fired up my project last night after carefully checking all my solder connections, etc. and all was well, including the display of data on my Parallax serial 4x20 LCD.
As I brought various components of the project on-line 'something bad happened' (still don't know what, exactly), and my LCD panel quit displaying data from the BS2. It runs o.k. in test mode, but when sending even the simplest text strings at any baud rate, all that displays is the un-moving cursor. With a logic probe I can confirm serial data is arriving, but I can't find it anywhere on any of the daughterboard's exposed components or pins.
Hoped to find a schematic for the device and see if I could find an obvious and quick fix, but no luck there.
I do have a 2x16 LCD that displays the data coming from the BS2, so I know it's the LCD and not the BS2 or its code.
Question 1: Is it worth trying to track down a schematic for the 4x20 LCD daughterboard and attempting a repair?
Question 2: The daughter board on the 2x16 looks suspiciously like the one on the 4x20. Only obvious difference is the one on the 2x16 is labelled "Rev C", and the one on the 4x20 is labelled "Rev E". Any chance I can simply swap the daughterboards and salvage my 4x20 display?
Or, am I just out of luck and will have to order a new display?
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M. Kibat
Bloomington, MN
kibatme@visi.com
As I brought various components of the project on-line 'something bad happened' (still don't know what, exactly), and my LCD panel quit displaying data from the BS2. It runs o.k. in test mode, but when sending even the simplest text strings at any baud rate, all that displays is the un-moving cursor. With a logic probe I can confirm serial data is arriving, but I can't find it anywhere on any of the daughterboard's exposed components or pins.
Hoped to find a schematic for the device and see if I could find an obvious and quick fix, but no luck there.
I do have a 2x16 LCD that displays the data coming from the BS2, so I know it's the LCD and not the BS2 or its code.
Question 1: Is it worth trying to track down a schematic for the 4x20 LCD daughterboard and attempting a repair?
Question 2: The daughter board on the 2x16 looks suspiciously like the one on the 4x20. Only obvious difference is the one on the 2x16 is labelled "Rev C", and the one on the 4x20 is labelled "Rev E". Any chance I can simply swap the daughterboards and salvage my 4x20 display?
Or, am I just out of luck and will have to order a new display?
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M. Kibat
Bloomington, MN
kibatme@visi.com
Comments
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Jon Williams
Applications Engineer, Parallax