??? 03/06/07 19:25 Read: times |
#134409 - A little bit of sarcasm as usual but often helpful Responding to: ???'s previous message |
Erik Malund, this is not the first time you have responded to my question, but have been a tremendous help to some of my other questions which i could not have made it without you help, albeit a little sarcastic at time :) But it is all good. A rare gem among other 8052.com forumers i can say. Thank you!
Now let's get back into question : you can not just jump into coding, you need to knoe the basics first. Where do you initialie the UART, what inteface do you use, you ask about totally impossible assembler instructions.... Yes, i have thought of the initiazation and i do not, by any means blindly jump into the pool without knowing how to swim. As i have already mentioned, the configuration of the modem is assume to have been properly set and is now ready to accept command. The configuration being assumed done here is resetting TI/RI flags, setting the baud rate by means of using the auto-reload of Timer 1(i still do not know what is the proper baud rate to be used though), configuring TCON, SCON, etc. FIRST How does a Pin 3.1 which is also called as TxD differs from other port if i want get familiar with "the bible" ch 3 has lots of stuff on the UART. I have done some deeper research *again* with "the bible" and i now know that Pin 3.1 has the SBUF capability to store and send out a single byte at a time and thus saving programmer time from coding the data transmission from the scratch using bit by bit method. THEN a byte of data out from the TxD (P3.1) to a modem verify that your modem is TTL or RS232, if TTL it is a wire, if it is RS232 you will need a MAX232(equivalent) between the uC and the modem. It is using RS232 interface using MAX232 and yes, i have take account of the communication line needed to be done between the modem and the 8051. So far, the only pin needed to be used is the TxD and RxD on both 8051 and the DB9 connector. The only thing i have left now is to communicate properly with the modem by means of sending a string of any AT Command to it. I already have the AT Command set of the modem and once the method of communication is taken care of, i can proceed with the operation of the modem hopefully by myself. Lastly but not least, thank you very much for the helpful links i will take a look into it as soon as possible. |