Mtk 6989

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Elgin Carmona

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Aug 3, 2024, 5:30:47 PM8/3/24

to caezuperdawd

While I'm trying to learn the source code (hal_LCD.c), I do not quite understand what the values represent in the second column in the 2D arrays: (I do know where to get the values for the first column)

in the MSP-EXP430FR6989 Launchpad User's Guide www.ti.com/.../slau627, you can observe that for each digit on the display, there are a total of 4 pins (4 rows of the mapping) to control every segment in that digit.

So for example, the A1 digit on the left side of the display is controlled by pins 1-4, the first 4 rows of the table. Each row represents 4 bits of data to control it (the 4 columns), for 16-bits total to control the entire digit. This is why 2 bytes are needed to fully set each digit. You can see from the mapping table and the segment layout, that the primary segments to display something are mostly stored in the first 2 rows = first byte. But some letters, e.g. the letter K, use the diagonal segments - you can see that these diagonal segments, e.g. A1K and A1N, are in the 3rd and 4th rows = second byte.

Does this help to clear things up?

Regards,
Katie

On the MSP-EXP430FR6989 LaunchPad User's Guide ( ) Table 3 on Page 12 there is a list of the LCD segments for each Digit. On there, each Digit has an ending character to it that designates which segment will light up. Those are what are used to map out the two columns.

The image below is a photograph of NGC 6989 from the Digitized Sky Survey 2 (DSS2 - see the credits section) taken in the red channel.The area of sky represented in the image is 0.5000x0.5000 degrees (30.00x30.00 arcmins).