LCD serial backpacks

[flipper_md]

Apparently, It will lock the PIC from receiving commands, if external data is received before it enter the main loop.

Visually, It will flash the LED, show "LCD Serial - READY", but stop there and not respond.


may I suggest Dr Pepper ?
Sugar is food for the brain

[timseven]

Yes Mr. Taylor I can't forget Joe S. as this backpack originator, I am sorry.

Well, I am almost there. I had some lines modified to the program to adapt it to my hardware. I modified:
DEFINE LCD_LINES from 4 to 2. ‘My LCD is 2X20
DEFINE OSC from 20 TO 4 ‘My 628 is 4 Mhz
DEFINE HSER_SPBRG from 32 to 25 ‘My 628 is 4 Mhz
The rest is unchanged.
When I turned it on I got the “Your text goes here” message and then over it a second later I got “Clearing display buffer” error. It’s something else that I need to change on the program to prevent the buffer to overrun? Thanks.

[Darrel Taylor]

Change TXSTA to ...

DEFINE HSER_TXSTA 24h

9600 baud at 4Mhz needs the BRGH bit set to 1 with SPBRG = 25.

[timseven]

I did the change on “DEFINE HSER_TXSTA from 20H to 25H and tested with same error. I restored all the DEFINES back to its original values (DEFINE OSC 20, DEFINE HSER_TXSTA 20H, DEFINE HSER_SPBRG 32) and used this time a 628-20 Mhz chip. I got the same error “Cleaning Display Buffer”. Any suggestion?

[Darrel Taylor]

Maybe it was just a typo, but TXSTA should have been changed to 24h, not 25h. But it probably wouldn't matter.

And when you say "and used this time a 628-20 Mhz chip"...
Do you mean that you used a 16F628 with a 20Mhz crystal and two 15-33pf capacitors?

[flipper_md]

Tim,

are you sending data to the screen to see if the message will clear out?

I always see the clearing display message at start, but everything works fine when I send data (without my silly Disabled Interrupt trial..of course).

[timseven]

Yes, was a typo I mean 24h. Yes, I used a 16F628-20 Mhz. I changed the crystal but not the caps, sorry. Mr. Flipper_ND, when I received the error I thought I shouldn’t go on, but I think that you got a point there, I’ll. First I’ll do the test with the two 15-33 pf caps in place and next test sending some data. I’ll report to both of you. Thanks.