- This topic has 4 replies, 4 voices, and was last updated 9 years ago by
.
-
Posts
-
Dear
sir/mamI am a BE final year student .I want to do project on send sms to a mobile using 8051 with gsm module .I have sim900 module and 89c51 and also program .Using pc gsm module is working perfectly and After loading the program in 8051 it is also working perfectly in putyy software and in hyper terminal but when i connect gsm with 8051 throw max232 ic it is not working.i need proper hardware connection so plz kindly help me how can i interface gsm module with 8051 .i’ll pay for that plz help me.
GSM modules has only 3 pins to be connected with micro controller
1 Tx
2 Rx
3 Gnd
see the datasheet of max232 chip to get the idea to connect micro contoller and gsm module through RS232
HEY A M BHATT, ihave tried to compile your code which you posted for robotic arm using gsm only to get an error l121: improper fix up.
what could be wrong. ihave copied pasted the program. help bhatt.
The project explains interfacing of the AT89C51 microcontroller with the GSM module and the HyperTerminal. HyperTerminal is a Windows application. The AT commands are sent by the HyperTerminal to the GSM module. The Information Response and/or Result Codes are received at the microcontroller and retransmitted to the HyperTerminal by the controller.A GSM module has an RS232 interface for serial communication with an external peripheral. In this case, the transmit pin (Tx) of the computer’s Serial port is connected with the receive pin (Rx) of the GSM module’s RS-232 interface. The transmit pin (Tx) of the RS-232 of GSM module is connected to receive pin (Rx) of microcontroller’s serial transmission pin. And the serial transmit pin of the microcontroller is connected to the receive pin of the computer’s Serial port. Therefore the commands and their results are transmitted and received in a triangular fashion as depicted below.
[In subsequent projects (see MC075 & MC076), the HyperTerminal will be replaced by the microcontroller itself; thus avoiding the need of using a Computer to establish an interface. This would lead to an independent GSM based system.]
The microcontroller is programmed to receive and transmit data at a baud rate of 9600. For more details on setting the baud rate of microcontroller, refer serial communication with 8051.The controller can receive data signals either by polling or by making use of serial interrupt (ES). Serial interrupt has been explained in interrupt programming. In polling, the controller continuously scans serial port for incoming data from the GSM module.In this project, interrupt has been used for monitoring and controlling the flow of data by the controller instead of the polling method.All credits to the original poster:I wish you luck
- You must be logged in to reply to this topic.