LCDout question

[rhino]

The LCD may be connected to the PICmicro MCU using either a 4-bit bus or an 8-bit bus. If an 8-bit bus is used, all 8 bits must be on one port. If a 4-bit bus is used, the top 4 LCD data bits must be connected to either the bottom 4 or top 4 bits of one port. Enable and Register Select may be connected to any port pin. R/W may be tied to ground if the LCDIN command is not used.

I thought it might have to do with the amount of current the lcd draws and how much the micro can take, but I could be wrong. Looks like you might have to cut some traces, and reroute with with "wires of shame".

[MikeTamu]

Well, I know the hardware (PIC18F252) is capable of running the LCD with my current setup. I designed the board with a Dios 28 pin microcontroller http://www.kronosrobotics.com/xcart/...roductid=16169 which is simply a PIC18F252 with a built in Basic compiler in one package. Kronosrobotic's Basic compiler has no problem in allowing any port on the MCU to be used for any pin on the LCD. I have my current configuration working in front of me with the Dios 28 mcu.

However, for economic issues, I wanted to be able to switch to PBP. So, if the hardware permits my configuration, why doesn't PBP allow it? I assume MElabs wants a robust compiler, so I am not sure why there is not provisions in the compiler to allow LCD pin switching on permitting PICs.

I guess I will have to write my own Hitachi LCD interface. I don't know what other options I have at this point.

[NavMicroSystems]

MikeTamu,

PBP does allow it,
but you'll have to write your own "LCDOUT" Routine.

See this thread

[MikeTamu]

Thanks, somehow I missed this thread in my search.

Thinking more on the matter I found a solution that has been glaring me in the face this whole time. I can just edit some wires on the cable going to my lcd screen, and thus rename ports. Luckily I happen to get at least the upper 4 bits of portb on my interface.

However, I am still interested in making a user friendly 'all-in-one' lcdoutX routine for future problems if they come up.

[NavMicroSystems]

...However, I am still interested in making a user friendly 'all-in-one' lcdoutX routine for future problems if they come up.

Well, if it just a single shot (on an existing board) I would spend $2 and use another PIC as "serial backpack" for the LCD. (and free up some PIC Pins)
Or rewire some pins.

If we are talking about higher quantity I would design the Hardware to meet the requirements of my development tools in the first place.

[MikeTamu]

Correct.

Unfortunately, I was not introduced to PBP until after this board was designed. The board was designed with a 3rd party brand microcontroller which is a repackaged PIC.

It is low quantity and I have learned a valuable lesson here. I think for now a cable fix will suffice.