Hi guys


I am trying to use a BV4612 Keypad/LCD as a control panel for an alarm system.

I am controlling this from the serial port using the Windows software 'Profilab Expert'.
I can input a numerical code and display it on the screen:



so far so good.

Problem is I can't find how to backspace/delete the last character in case of a wrong keypress. The display doesn't respond to the usual backspace Command (0x08).Do I need to re-write the whole screen (without the last character) or can I re-write just the one line, or is there a backspace command that will work? I can't find any reference in the datasheet.

Also I want to set the keypad to output the data directly without using the buffer.
I can successfuly change the indicator flag but even though the relevent bits appear to be set the keypad still uses the buffer. Am I overlooking something here?

Any help or advice will be much appreciated

Thanks in advance
Dave



Edited 2 time(s). Last edit at 09/13/2015 10:53PM by Dave L.

hello,
there is no built in back space. The code would be something like:
assume '4' is at rc(4,90)

rc(4,90)
print(" ")
rc(4,90)
.... new number

The direct output from the keypad only works with the serial interface and is a recent addition and only applies to version 1.5.

Using a serial interface:
jV should report 1.5 or above
jW,3,48 set bits 4 and 5 to 11 (0x30)
jC always reset after updating eeprom

It is not a user option but possible to update the firmware.

Hi Jimeer

Thanks for the swift reply

Printing a 'space' works fine as long as I keep track of where the cursor is.... should have thought of that myself!

I am having no luck with the indicator flag though.

Firmware is v1.6

I am using the serial interface and I can change the flag and this is remembered after a reset, but the buffer is still filling up and the key pad isn't sending data.

The project is still usable as it is but makes it more complicated having to constantly poll for keypresses and read the buffer, as the software I am using (Profilab) can get quite resource hungry especially when constantly clocking.

I will capture the data and post screenshots, maybe I am overlooking something.

once again Thank You for your help
Dave

I will look into this
Jim

Hello again

Here is a data capture of me changing the indicator flag from 52 to 48:



It appears to be changing successfully but the keypad still fills the buffer, it's just as though the feature isn't implemented!

Thanks again for looking into this
Dave

Thank you for your patience, There is an error in firmware 1.6 that stops the feature working so you will need an upgrade. to 1.7. Can you contact me via email to arrange it.
Jim

Hi Jim

That explains it then... I've been scratching my head for days thinking I was missing something simple!

PM sent

Dave