HG12603-A LCD display


New member
I have a HG12603-A LCd display.its 24 x 8 i have it all wired up with a MAX232 IC and plugged into COM1. i turn my computer on and it flashes some words, but i cannot see what it says . and then if blinks

"Dir1 Remind InLog Dial DiLog"

any idea on why it is doing this??
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CF Tech

I think the answer is here:


Depending on which display you have, IC9 will either be the original AT&T PROM or an AMD AM29F010B FLASH device. If you have a 29F010B then chances are your board has been programmed with the PJRC firmware and fonts. If you still have the AT&T PROM, then you need to remove it and replace it with a 29F010B with the PJRC firmware.
With things like "dial" coming up, I think you must have the original AT&T PROM.

CF Tech

I do not know much about this LCD, but it looks like it is basically a surplus module that was pretty worthless, until someone wrote new firmware for it, which turns it into a pretty cool display.

I think you need that firmware. It will probably be a chip you need to get from someone that has the firmware loaded onto it, unless it can somehow be loaded onto the module.


New member
Interesting bug in this display

I recently bought few of those. However I have noticed that the LCD behaves funny if the same character is repeated over and over. In those cases the blank cells start to exhibit glowing dots that seem to be in pattern with the character displayed. This only happens in few characters - lower "p" and upper "I"

In the picture lower case 'p' causes a vertical line to glow.

Do you have any suggestions on this? Thank you