Real time clock ICs

[Jumper]

Hi,

I would like to add a 4k7 resistor between DS1307 (pin7) and 5V as a pullup resistor and as said many times before GND the backup battery pin.

[SteveB]

I haven't gone through the code completely, but taking another quick look at the schematic I noticed there aren't any pull-ups used for the buttons. I did see a TRISB=%11111111 in there, as well as checking one of the buttons low as a condtion in an IF...THEN statement used to enter the SetupEntryLoop (I am assuming the logic is the same on all three). So they are floating, and should be pulled-up. You could just use those 10K pull-ups you removed from the SCL/SDA lines (which should now have 4.7K) and add them to the pins for each of the buttons. Just need one additional for the third button.

Steve

[Melanie]

Gawd, that's a four-year-old program and you expect me to remember what LCD's I was using at the time? I do recall that you could use either the upper or lower 4-bits. On checking the current DATASHEET (Datasheets always seem to come into the conversation on this thread) I find that Tri-T (our currect supplier) only supports the UPPER four bits. So this is obviously non-standard. I'd connect as per the PBP manual, but using the Port pins as specified in the DEFINES within the program. I've tried the original MN1307 this morning (I've not checked the posted version) connected that way and it works.

Buttons are on PortB and use the PICs internal weak pull-up's.

[Eng4444]

The best thing is to have a huge project done ahead of time... everybody there is still working.

I checked all the comments i have. Thank you for your cooperation :-)

how would i know that they should have been D4 throught D7.... i do not work with electronics and i was doing exactly as it was said.

i will try all what was said in 2 hours and then give feedback.

i wish a nice day for everybody!

[Eng4444]

Seems we sent our posts in the same time!


SO you are saying that i can connect to the lower 4 bits as long as i keep the "defines" in the program?

And in case i will use from D4 to D7 i should change the "defines".
So what to change in this part if so?

"

Define LCD_DREG PORTA ' Port for LCD Data
Define LCD_DBIT 0 ' Use lower 4 bits of Port
Define LCD_RSREG PORTA ' Port for RegisterSelect (RS) bit
Define LCD_RSBIT 6 ' Port Pin for RS bit
Define LCD_EREG PORTA ' Port for Enable (E) bit
Define LCD_EBIT 7 ' Port Pin for E bit
Define LCB_BITS 4 ' Using 4-bit bus
Define LCD_LINES 2 ' Using 2 line Display
Define LCD_COMMANDUS 2000 ' Command Delay (uS)
Define LCD_DATAUS 50 ' Data Delay (uS)

"

i'll check this this thread when i arrive to my Lab.

By the way,
Don't you think people that this thread reached the highest score of visits?! hehe.

Let's reach the highest possible number! :-)

[Melanie]

There is a very basic software only (no RTC chip required) elapsed timer demo, ready to run, just an LCD and one Button only, at the bottom of this thread here...

http://www.picbasic.co.uk/forum/showthread.php?t=3423

[Eng4444]

Hello,

Here i arrived and will test your program....

honestly, i liked the first program because it gives time and date. I really hope it will work.

By the way, don't think that i will say that "i" did it. But i will show the source of it and all the posts and replies for this thread.

i really hope i'll ba able to see something on LCD.

First thing is that i will change the bits from D4 TO D7 and connect them to PIC; moreover, i will put 4.7 K resistors and 0.1uF Capcitors

More infos to come soon!

[Eng4444]

I connected all the circuit with the new changes and then downloaded the program after adding the following:

@ DEVICE pic16F628A, INTRC_OSC_NOCLKOUT
' System Clock Options
@ DEVICE pic16F628A, WDT_ON
' Watchdog Timer
@ DEVICE pic16F628A, PWRT_ON
' Power-On Timer
@ DEVICE pic16F628A, BOD_ON
' Brown-Out Detect
@ DEVICE pic16F628A, MCLR_OFF
' Master Clear Options (Internal)
@ DEVICE pic16F628A, LVP_OFF
' Low-Voltage Programming
@ DEVICE pic16F628A, CPD_OFF
' Data Memory Code Protect
@ DEVICE pic16F628A, PROTECT_OFF
' Program Code Protection

So now , when i compile with microcoe studio it compiles successfully. Bu when i want to program the IC, it gives a message :

" this program contains EEDATA - EDATA and this part will be discarded"

so i press "OK" and it begins programming.

during the process, when it arrives to " Programming EEDATA section" it stops and gives this message:
" Programming time-out or connection error"

For sure i have no connection error because i tried a small program on another IC and it worked.

any idea?

[Melanie]

Not from me, I don't use Microcode studio and avoid any questions on the topic.

If you compiled your MN1307.bas code from a DOS Window...

PBP -p16F628 MN1307 -v

or

PBP -p16F628A MN1307 -v

depending which version you're using... It will compile.

Likewise I can't comment on your method of programming the actual PIC.