I have finally found out how to resolve this problem. As I said in in the “Additional Information” section of my question, sending line ends with line feeds caused this mismatching between SerialPort in C# and AT commands in hyperterminal for sending Unicode messages. I have just replaced \r with \n line feeds. The modified … Read more
Maybe these quotes and links can help you code your own solution: 1.- To get a list of available network providers (quoting How to get a list of available network providers? in full): Since Android is open source I had a look at the sources and finally found something called INetworkQueryService. I guess you can … Read more
First, to increase your understanding of AT commands in general, read the V.250 specification. That will go a long way in making you an AT command expert. Then for the actual implementation, I do not know Codesys, so the following is pseudo code of the structure you should have for handling AT commands: the_modem = … Read more
I know three ways on how you can do it on iOS 5.x – 7.x. All of them use private APIs from CoreTelephony.framework. Supports both GSM and UMTS. 1) Using cell monitor struct CTResult { int flag; int a; }; extern CFStringRef const kCTCellMonitorCellType; extern CFStringRef const kCTCellMonitorCellTypeServing; extern CFStringRef const kCTCellMonitorCellTypeNeighbor; extern CFStringRef const … Read more
How do you get notified about, and acquire instances of GSM Calls First, the user will need to select your app as the default Phone app. Refer to Replacing default Phone app on Android 6 and 7 with InCallService for a way to do that. You also need to define an InCallService implementation the system … Read more
Start by acquiring a large A3 sheet of paper, find a red pen and write 1000 times I will never use delay as a substitute for reading and parsing responses from a modem. I will never use delay as a substitute for reading and parsing responses from a modem. I will never use delay as … Read more
You should never, never, ever use sleep as a substitute for waiting for the Final result code from the modem. Just as you would not write a http client that completely ignores all responses from the http server, you should not send AT commands to a modem and completely ignore the responses it sends back. … Read more
General note about your handling of AT commands. No, no, no! This way of doing it will never work reliably. You MUST wait for the > character to be received before sending “text to send”. Or actually it is not just the > character, it is four characters. Quote from 3GPP specification 27.005: the TA … Read more