hi. Can anyone tell me if this is a revision for the original board. (MKR1400 vs MKR1400B)?
If so, what has been revised.
I'm crossing my fingers for the deep sleep issues to be fixed.
Mat.
Bump. There was a schematic change in late Jan of 2019. I too would like to know what's changed since the original release. Is there an errata available?
How about some answers from the MKR development team since this is supposed to be the official help forum for MKR issues.
opened 08:24PM - 20 Nov 18 UTC
type: imperfection
I've posted this before, but I'll try again. My code is pretty simple. I check f… or SMS messages and then reply back using Hologram's network. I'm using the latest MKRGSM library 1.3.1. I also have a 1400 mAhr lithium battery connected so I'm confident that I don't have a hardware issue related to modem current.
Here's my code:
```
#include <MKRGSM.h>
const char PINNUMBER[] = " ";
const char GPRS_APN[] = "hologram";
const char GPRS_LOGIN[] = " ";
const char GPRS_PASSWORD[] = " ";
String HOLOGRAM_DEVICE_KEY = "********";
String HOLOGRAM_TOPIC = "_SOCKETAPI_";
GSMClient client;
GPRS gprs;
GSM gsm(1); // Enable debug
GSM_SMS sms;
GSMScanner scan;
char server[] = "cloudsocket.hologram.io";
int port = 9999;
boolean isSMSAvailable = false;
char sms_message[145];
void setup() {
Serial.begin(115200);
//while(!Serial);
scan.begin();
connectGSM();
}
void connectGSM() {
boolean connected = false;
while (!connected) {
Serial.println("Begin GSM Access");
if ((gsm.begin() == GSM_READY) &&
(gprs.attachGPRS(GPRS_APN, GPRS_LOGIN, GPRS_PASSWORD) == GPRS_READY)) {
connected = true;
Serial.println("GSM Access Success");
Serial.println(scan.getCurrentCarrier());
}
else {
Serial.println("Not connected");
delay(1000);
}
}
}
void loop() {
if(Serial.available()) {
char c = Serial.read();
if(c == 'e')
MODEM.debug();
if(c == 'd')
MODEM.noDebug();
}
// Get any new incoming txt messages
int c;
if (sms.available()) {
int i = 0;
while ((c = sms.read()) != -1) {
sms_message[i++] = (char)c;
}
sms_message[i] = '\0'; // Terminate message
isSMSAvailable = true;
sms.flush();
}
if(gsm.isAccessAlive()) {
if(gprs.status() != GPRS_READY) {
if(gprs.attachGPRS(GPRS_APN, GPRS_LOGIN, GPRS_PASSWORD) == GPRS_READY)
Serial.println("GPRS ready!");
else
Serial.println("GRPS not ready!");
}
}
else {
Serial.println("Reconnect to GSM...");
connectGSM();
}
// Send message back through hologram
if(isSMSAvailable) {
isSMSAvailable = false;
if (client.connect(server, port)) {
client.print("{\"k\":\"" + HOLOGRAM_DEVICE_KEY + "\",\"d\":\"");
client.print(sms_message);
client.println("\",\"t\":\""+HOLOGRAM_TOPIC+"\"}");
client.stop();
}
else {
MODEM.send("AT+USOER");
}
}
delay(1000);
}`
```
It takes anywhere from a few days to a week or more to exhibit the problem. My logs typically look like this, where the incoming SMS message, "Jdjd", gets received and then repeated back to me via Hologram's network.
```
OK
AT+CMGL="REC UNREAD"
+CMGL: 19,"REC UNREAD","+19495472010",,"18/11/14,03:53:24+00"
Jdjd
OK
AT+CMGD=19
OK
AT+CREG?
+CREG: 0,5
OK
AT+USOCR=6
+USOCR: 0
OK
AT+USOCO=0,"cloudsocket.hologram.io",9999
OK
AT+USOWR=0,21,"7B226B223A22433E383375242B57222C2264223A22"
+USOWR: 0,21
OK
AT+USOWR=0,4,"4A646A64"
+USOWR: 0,4
OK
AT+USOWR=0,20,"222C2274223A225F534F434B45544150495F227D"
+USOWR: 0,20
OK
AT+USOWR=0,2,"0D0A"
+USOWR: 0,2
OK
AT+USOCL=0
OK
AT+CMGL="REC UNREAD"
OK
AT+CREG?
+CREG: 0,5`
```
However, after a week or so this happens:
```
`OK
AT+CMGL="REC UNREAD"
+CMGL: 19,"REC UNREAD","+19495472010",,"18/11/20,19:51:00+00"
JDJDJ
OK
AT+CMGD=19
OK
AT+CREG?
+CREG: 0,5
OK
AT+USOCR=6
+USOCR: 0
OK
AT+USOCO=0,"cloudsocket.hologram.io",9999
ERROR
+UUSOCL: 0
AT+USOCL=0
ERROR
AT+CMGL="REC UNREAD"
OK
AT+CREG?
+CREG: 0,5
OK
AT+CMGL="REC UNREAD"
OK
AT+CREG?
+CREG: 0,5
````
From then on, the library is never able to recover.
Any help would be greatly appreciated. The code I submitted is a stripped down version of my application. I've been wanting to release my application using the MKRGSM board but I've been haunted by this issue. I see there's some asynchronous options that aren't well documented and I'm reluctant to use this approach - besides, shouldn't this library be rock solid as documented!
Seems like the only change was the removal of a fuse in series with the battery. From various discussions it appears the fuse resulted in too large a voltage drop during transmission to 2G networks.
Too bad, it would have been perfect if they had made that last connection to pin 35, I2S_TXD to enable bi-directional audio communications. I'm curious as to why they would omit such a simple necessity. After all, it is a GSM cell phone. What possible reason could there be for not allowing it to be used as one?
Mike