Making Code Smaller for a Multiplexed LCD Display

[rsocor01]

Even if it could, the underlying code will still have to do the same hard work of juggling bits around.

Yeap, you are right. I was hoping that somebody knew of a clever way of doing this.

[mark_s]

Hello

Which pic are you using? There are some newer chips like the 16f1939 with 1k ram and 16K of program space. There are 18f with double.

[rsocor01]

Hello

Which pic are you using? There are some newer chips like the 16f1939 with 1k ram and 16K of program space. There are 18f with double.

Actually, I'm using the 16F1939. I'm going to check for the 18F that you mentioned.

[Art]

I think it’s tough, but a curiosity now,

    LCDDATA11.1 = PATTERN.7

How did you define these?
Is PATTERN a single byte you are looking at bits 0-7,
and LCDDATA, there are 11 bytes, and you look at bits 0-7 of all 11 bytes?

I’ve not used that syntax before, but PATTERN.bit7 (to address a bit), or PATTERN[7] (to address a byte).

[rsocor01]

Art, in this example there is a multiplexed 7-segment LCD, 4 commons, display that I am running directly from the PIC. The advantage of the 4 commons is that you only need one pin in the PIC for every 4 segments of the display, so you minimize the number of needed pins.

The byte PATTERN changes its value for everyone of the 8 digits of the display. After enabling the LCD feature in the PIC, you need to load LCDDATA the registers for it to work.