help with 4 x 20 LCD

[keithv]

Just FYI, this is the LCD Module I'm using.

I've got it connected just like the LAB-1X:

VSS > ground
VDD > +5v
V0 > ground
RS > RE0
R/W > RE2
E > RE1
D0 > RD4
D1 > RD5
D2 > RD6
D3 > RD7
D4 > RD0
D5 > RD1
D6 > RD2
D7 > RD3
A > +5V
K > ground

[richard]

seems a strange way to connect it
I would
D0 > gnd
D1 > gnd
D2 > gnd
D3 > gnd

plus r/w can be grounded
it you connect it to e2 then that needs to be defined for correct operation
Define LCD_DREG PORTD
Define LCD_DBIT 4
Define LCD_RSREG PORTE
Define LCD_RSBIT 0
Define LCD_EREG PORTE
Define LCD_EBIT 1
Define LCD_LINES 4 'code works in LAB-X1 without this line
DEFINE LCD_RWREG PORTE 'LCDOUT/IN read/write port
DEFINE LCD_RWBIT 2 'LCDOUT/IN read/write bit

and vo is connected to wiper of contrast pot (10k) that's connected between vcc-gnd

with vo grounded thats max contrast and display shows all black squares