I²C and RS232 on the same PIC - Electronic Circuits Projects Diagrams Free

l30 · 28th June 2004, 12:44 AM

Ok friends, first of all, sorry for my bad english, it's not my primary language.

I have an average knowledge of analogic eletronic, but just a little of digital, and need some help on a project. I have to READ and WRITE data from a Real Time Clock (in case, a DS1307) using a PC. I've tryed to do it without a uC, but can't make it work so I decided to use one.

I want run an application (that part - send and receive data from the RS232 on the PC side isn't a problem) on my PC that will send via RS232 a command to the PIC saying:"Write the date/Time XXXXXXXX on the RTC", and the PIC will WRITE it via I²C to the RTC.
Or I will say "Read the Date/Time of the RTC" and the PIC will read it and send it to my application via RS232.
From my researches i found out that a PIC16F628 would be the right choice. Am I right?

It is possible to do that? HOW?
If someone can help me with the code and connections, send me some links, tips, anything would help.
I have seen som examples on how to read/write on I²C EPROMS, and was thiking if I can use a similar schematic, but the main problem than it's the uC code.... please, if some of you have the time to help, i'll apreciate a lot.

i have just found this link:
CODE:
http://web.ukonline.co.uk/j.winpenny/pic/i2c.txt
SCHEMATICS:
http://web.ukonline.co.uk/j.winpenny/pic/e2test2.gif

looks like what i need, but not sure about the RS232 part... looks like it is not implemented on the CODE...any idea?

thanks

Exo · 28th June 2004, 12:55 AM

Nigel's site has scematics and code to do RS232 on a 'F628
www.winpicprog.co.uk

glmclell · 3rd July 2004, 04:14 AM

This might be what you are looking for??

App Note 206: Using a PC's RS-232 Serial Port To Communicate with 2-Wire Devices
http://www.maxim-ic.com/appnotes.cfm...te_number/1096

the document is a "how-to" for using a cheap PIC to be a translator between PC and SMBus / I2C ... they even include a windows interface program (with code) and a pre-compiled HEX (with source) for a PIC16FL628

-----
just fyi here is a run down of my serial interface project on a PIC18F series!

pic 18F452 that is currently utilizing 4 serial buses:

Serial output to a serial LCD using a general purpose pin
Dallas 1-Wire I/O using a single general purpose pin
I2C Master Mode I/O using the pic's hardware MSSP ports (2 pins)
RS232 via a max232n using the pic's hardware USART ports (2 pins)

there is an occasional glitch with the rs232 when I try to write to the LCD and the RS232 at the same time, haven't quite figured that out

I'm using Proton PicBasic Plus ... there is a free version on their website that might fit your needs.

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28th June 2004, 12:44 AM	#1
l30	I²C and RS232 on the same PIC Ok friends, first of all, sorry for my bad english, it's not my primary language. I have an average knowledge of analogic eletronic, but just a little of digital, and need some help on a project. I have to READ and WRITE data from a Real Time Clock (in case, a DS1307) using a PC. I've tryed to do it without a uC, but can't make it work so I decided to use one. I want run an application (that part - send and receive data from the RS232 on the PC side isn't a problem) on my PC that will send via RS232 a command to the PIC saying:"Write the date/Time XXXXXXXX on the RTC", and the PIC will WRITE it via I²C to the RTC. Or I will say "Read the Date/Time of the RTC" and the PIC will read it and send it to my application via RS232. From my researches i found out that a PIC16F628 would be the right choice. Am I right? It is possible to do that? HOW? If someone can help me with the code and connections, send me some links, tips, anything would help. I have seen som examples on how to read/write on I²C EPROMS, and was thiking if I can use a similar schematic, but the main problem than it's the uC code.... please, if some of you have the time to help, i'll apreciate a lot. i have just found this link: CODE: http://web.ukonline.co.uk/j.winpenny/pic/i2c.txt SCHEMATICS: http://web.ukonline.co.uk/j.winpenny/pic/e2test2.gif looks like what i need, but not sure about the RS232 part... looks like it is not implemented on the CODE...any idea? thanks

28th June 2004, 12:55 AM	#2
Exo	Nigel's site has scematics and code to do RS232 on a 'F628 www.winpicprog.co.uk

3rd July 2004, 04:14 AM	#3
glmclell	This might be what you are looking for?? App Note 206: Using a PC's RS-232 Serial Port To Communicate with 2-Wire Devices http://www.maxim-ic.com/appnotes.cfm...te_number/1096 the document is a "how-to" for using a cheap PIC to be a translator between PC and SMBus / I2C ... they even include a windows interface program (with code) and a pre-compiled HEX (with source) for a PIC16FL628 ----- just fyi here is a run down of my serial interface project on a PIC18F series! pic 18F452 that is currently utilizing 4 serial buses: Serial output to a serial LCD using a general purpose pin Dallas 1-Wire I/O using a single general purpose pin I2C Master Mode I/O using the pic's hardware MSSP ports (2 pins) RS232 via a max232n using the pic's hardware USART ports (2 pins) there is an occasional glitch with the rs232 when I try to write to the LCD and the RS232 at the same time, haven't quite figured that out I'm using Proton PicBasic Plus ... there is a free version on their website that might fit your needs.