sid v2 + 8bit LCD ?

MIDIbox SID
1

Hi,

i am building a sid v2, with 1 core and 2 sids.

only ! core, so i don’t really need the CAN connection.

so my question is: could i connect the LCD in 8bit (using all the pins on core J15) instead of 4bit, since i don’t need CAN ?

in a previous thread i read about a compile option in mios.h

#if PIC_DERIVATIVE_TYPE == 4
	LIST P=PIC18F4685, R=DEC
#include <p18f4685.inc>
#define PIC_DERIVATIVE_CODE_SIZE	0x18000
#define PIC_DERIVATIVE_RAM_SIZE 0xd00
#define PIC_DERIVATIVE_EEPROM_SIZE	0x400
#define PIC_DERIVATIVE_IRQ_WORKAROUND	0
#define PIC_DERIVATIVE_T08BIT_INVERTED	0
#define PIC_DERIVATIVE_SET_LCD_4BIT	1
#endif

i guess i would need to change PIC_DERIVATIVE_SET_LCD_4BIT  to 0 ?

any chance that it could work ? or am i having the wrong idea ?

thanks!

(oh, btw i wonder if my lcd is a pled type ? i would say no, but i am not sure. i bought that one:

http://character-lcd-lcds.shopeio.com/inventory/details.asp?id=1143&cat=Lcds&sub=Character%20Lcd)

2

The “compile option in mios.h” is for controlling the compilation of MIOS.

It is MIOS which will default to 4-bit mode for LCDs when the PIC is PC18F4685. So it is best to leave it alone and use 4-bit mode and not recompile MIOS.

If at some point you discover that display does not like 4-bit mode (unlikely) then you can use a custom LCD driver to connect it in 8-bit mode. But there’s no need to use 8-bit mode until you have a problem with 4-bit mode.

3

ok, i understand now. thanks wilba. :slight_smile:

4

Sidenote: there isn’t really an performance impact when using 4bit mode

Best Regards, Thorsten.

5

oh, i was not really worried about performance. i was just being a bit lazy and wondered if i could simplify the spaghettis inside the box.  :slight_smile:

6

Type: Yellow STN

Not a PLED, just your standard Super-Twisted Nematic LCD.

7

Not a PLED, just your standard Super-Twisted Nematic LCD.

thanks, you confirm my guess. i think i understood the difference now.

cheers :slight_smile: