LCD cable length?

[Art]

Problem Solved!!!

Here's the current circuit I was describing with the LCD data bus obviously omitted:



It does drive a 12 Volt relay this way if the other end of the relay coil is connected to a 12 Volt source.



.................................................. ...............................


I used the same transistor to switch the positive line to the LCD this way:



I could always use the first circuit to drive a relay that in turn switches the LCD,
but that wouldn't be very solid state would it?

Q for Darrel, Does resetting the FLAGS var affect any other PBP related stuff?
I have my own flags set and variables stored in RAM while I'm turning the VFD on & off.
It's working perfectly, but I don't want it to break anything else software-wise.
Cheers, Brek.

[Darrel Taylor]

Clearing the FLAGS variable will not affect anything else.
There are some I2C bits in there, but they are only used during an I2CREAD/I2CWRITE command.

The only time it could be bad is from within an interrupt handler, since an I2C command may have been interrupted.

[Art]

Great, no plans for I2C for this project Thanks for all your help too.

Oh, and before I forget.... This:

For old time sake!!

Still waiting for a sine wave version in that old odometer thread.
I used a pseudo sine lookup table to get the next vertical offset when I did it on my LED scroller.

LOOKUP si,[0,0,1,1,2,2,2,3,3,4,4,3,3,2,2,2,1,1,0,0],offset

Anyways, the rolling clock gets to stay it isn't blocking execution.

[Darrel Taylor]

Cool, I'm glad the odometer display got some use.

I tried the wavey one, but never did figure out a good way to do it.

[Art]

Tried it, it looked silly.
You just add something like this:

LOOKUP si,[0,0,0,1,1,1,2,2,2,3,3,3,4,4,4,5,5,5,6,6,6,6,5,5,5,4,4,4,3,3,3,2,2,2,1,1,1,0,0,0],offset'
si = si + 1
IF si = 41 THEN si = 0

before you lookup the eeprom address where the character tables are on eeprom.
add offset to the address you're reading from. Not worth it for LCD though I think.

[Art]

Greater than 5 metres of 10 conductor shielded computer cable wired across
a dashboard, to a compartment in the back of a large vehicle