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10 years, 4 months ago.
To Wei Zou
Hi Sir,
May I ask you a few things?
1. Is my connection right or wrong?
Mbed GPRS Shield
-VU to VIN
-GND to GND
-p9 to D0
-p10 to D1
2. May I kindly ask you that : Could I have a picture or a diagram of how you connect Mbed to Seeed GPRS Shield V2.0?
3. One more thing is: I do not know my SIM Card voltage type, whether it is 3V or 1.8V or 5V sir.
4. I do not insert the battery at the battery holder.
I used main.cpp program the one that you wrote.
- include "mbed.h"
- include "GPRSInterface.h"
/ On many platforms USBTX/USBRX overlap with serial on D1/D0 pins and enabling the below will interrupt the communication.
- You can use an LCD display to print the values or store them on an SD card etc.
- / Serial pc(USBTX, USBRX);
/**
- D1 - TX pin (RX on the WiFi side)
- D0 - RX pin (TX on the WiFi side)
- 115200 - Baud rate
- "apn" - APN name
- "username" - APN username
- "password" - APN passowrd
- /
GPRSInterface eth(D1, D0, 115200, "shppd", "", "");
int main() { printf("Hello\n"); wait(3);
Initialize the interface. If no param is passed to init() then DHCP will be used on connect() int s = eth.init(); if (s != NULL) { printf(">>> Could not initialise. Halting!\n"); exit(0); }
printf(">>> Get IP address...\n"); while (1) { s = eth.connect(); Connect to network
if (s == false || s < 0) { printf(">>> Could not connect to network. Retrying!\n"); wait(3); } else { break; } } printf(">>> Got IP address: %s\n", eth.getIPAddress());
Prepare the http request to mbed.org char http_cmd[] = "GET /media/uploads/mbed_official/hello.txt HTTP/1.0\n\n"; TCPSocketConnection sock; sock.connect("mbed.org", 80); sock.send_all(http_cmd, sizeof(http_cmd)-1); printf(">>> Sent request to mbed.org\n");
Read the response char buffer[300]; int ret; while (true) { ret = sock.receive(buffer, sizeof(buffer)-1); if (ret <= 0) break; buffer[ret] = '\0'; printf(">>> Received %d chars from mbed.org:\n%s\n", ret, buffer); } sock.close();
Disconnect from network eth.disconnect(); return 0; }
I am really looking forward to your reply Sir.
Thank you so much. I really need your help.
Regards Dorothy
Question relating to:
1 Answer
10 years, 4 months ago.
the main.cpp above is not written by me, it is writen by Mihail Stoyanov, and mine is https://mbed.org/users/lawliet/code/Seeed_GPRS_Library_HelloWorld/file/46f9e36be3fa/main.cpp. you can refer to it. If it still can not work, please use the serial debug to check that whether GPRS Shield can work at AT commands.