144 LED Games Console Project

[tmorgan4]

To Art: Thanks for posting this project and providing the code for others to use on their own projects. It has been a tremendous help.

I'm trying to avoid asking for a handout however I've run into several issues trying to build this this gaming console with a few modifications. I am new to programming PICs and other projects are likely easier to start with, however, I think with a few suggestions from others with more experience I'm hoping to make this work.

Instead of using a 16F877 I opted for the newer 16F887. I'm also using two of the 8x8 LED matrices from SparkFun for a total of 128 LEDs (8x16) as opposed to the 144 LED (8x18) display that the code was written for.

I'm hoping to use the internal 4Mhz clock of the 16F887 to allow more I/O pins for other devices. This can be changed in the code relatively easy but I'm unsure whether using a 4Mhz clock will cause unforeseen issues since console was designed around a 20Mhz oscillator.

I'm also trying to figure out how the rows and columns are defined in the code. I need to make changes since I have two less rows of LEDs (if playing tetris, vertical display) but I'm having issues deciphering how the rows and columns are defined.

If anyone has any suggestions I could use push in the right direction. Also, please post if you notice any other issues or changes that will be necessary when using the 16F887 in place of the 16F877.

Thanks in advance!

[Art]

Hi, I don't check in often unless I'm writing for pics at the time...

I'm going to get ports wrong if I guess here, given that it's years old now,
so just to describe how the rows and columns are defined... the display is
8 LEDs high to fit one column in a byte, so since it's a mono colour display,
the whole display buffer is 18 bytes
I use in line assembler (if I remember correctly), or an asm/PBP combination
to address the bits of each byte in each column.
C0 - C17 are the bytes for each column, they are being strobed in the draw screen routine.