Still digging on the subject ...
Today I took my original Fasttech OVMS v2 antenna out of my Nissan Leaf and connected it to the OVMS v3 in our VW e-Up. And surprise, surprise I got direct connection over the SIM to the network.
The VW antenna gives me -101 dBm, the Fasttech antenna gives me -91 dBm.
So I took a look at the frequencies ...
The old fasttech antenna has a frequency range of 824-960 / 1710-1990.
o2 (my SIM card provider) uses GSM 900 and GSM+LTE 1800 for 2g (4g LTE cannot be used on the SIM5360) and uses UMTS 2100 for 3g.
Now I have two theories on what make things go wrong with the VW antenna, but work with the fasttech antenna:
1. My home made sma / fakra adapter cable to the VW antenna is bad (could be, but in the city it connects)
2. Because 3g on 2100 mHz is not available through the fasttech antenna, OVMS v3 is forced to 2g and everything runs fine.
Any corrections on the second theory are welcome. I'm guessing ...
I will buy an other sma 2g/3g antenna just to get rid of the problem, but will also continue thinking on this one.
Greetinx
Chris
Am Montag, den 03.08.2020, 12:31 +0200 schrieb Chris van der Meijden:
Hi Michael
yeah, economical visionaries are always a lot of fun :-))
I read that "GSM voices services" line too and checked on that with my mobile phone. I restricted the connection of the phone with *#*#4636#*#* to "GSM auto (PRL)" and it connects to EDGE. So data over GSM is available ...
Still mysterious. Will dig some more ...
Greetinx
Chris
Am Montag, den 03.08.2020, 12:21 +0200 schrieb Michael Balzer:
Chris,
we don't tell the modem to restrict itself in any way. Bugs in the
modem firmware are likely, but I think a serious bug like this would
have been solved early.
I've read the pilot description now, and you need to pay attention
to this section:
statt der üblichen drei Dienste LTE, UMTS
und GSM kommen in Kirchfarrnbach "nur" LTE 800 und LTE 900 für die
Datenversorgung sowie GSM für Sprachdienste und SMS zum Einsatz.
Auf UMTS haben die Funknetzplaner hier verzichtet, weil bereits
LTE und GSM alle Anforderungen der Bevölkerung erfüllen.
…translated…
Instead of the usual three services LTE,
UMTS and GSM, "only" LTE 800 and LTE 900 are used in
Kirchfarrnbach for data supply as well as GSM for voice services
and SMS. The radio network planners have dispensed with UMTS here
because LTE and GSM already meet all the requirements of the
population.
So you have neither UMTS nor EDGE. GSM is only available for voice
streams and SMS. Data is only available via LTE.
Your only option is to tell them they're a bunch of … outstanding
economical visionaries, who could possibly consider rethinking their
IoT compatibility ;-)
Regards,
Michael
Am 03.08.20 um 11:33 schrieb Chris van
der Meijden:
I did some more reading on the SIM5360 and also digged a bit
through the simcom source. Found loads of AT-commands there :-)
I could not find an AT command to restrict the selection to
2g. Perhaps I did not look deep enough, but if someone knows the
command ...
I'm still thinking why the automatic fallback to 2g does not
happen.
- The transmitter offers only 2g (GSM 900 mHz) and LTE (800
or 1800). No 3g.
- I have a signal strength of -110 to -100 dBm
- AT+COPS? gives me an empty response.
Could it be possible, that somewhere in the code something
like
- I don't have 3g
- I do have LTE
- Lets try LTE
- I see LTE
- I have no hardware for LTE
- OK, don't do anything
happens? So somehow fallback to 2g never happens?
Just guessing around ...
Regards
Chris
Am Montag, den 03.08.2020, 10:10 +0800 schrieb Mark
Webb-Johnson:
The SIM5360E should auto-switch between 2G
and 3G. It supports the following frequency bands:
GSM/GPRS/EDGE
850/900/1800/1900MHz;
UMTS/HSPA+
900/2100MHz
There are SIMCOM options/commands to restrict the
selection, but the default is automatic.
Regards, Mark
Hey Michael
Thanx for the help :-)
The AT commands are working now, but as
expected no connection at all. So also no fallback
to 2g. Or no GPRS offered on 2g ...
Here some (German) information on the
"site lite" transmitters:
I also did not find any AT command for
the SIM5360 to force 2g. I will play a bit around
with the modem in the next days. Will also try
congstar, I do have a congstar SIM laying around
here ...
Greetinx
Chris
Am Sonntag, den 02.08.2020, 10:59 +0200
schrieb Michael Balzer:
Chris,
how to send modem commands and read the responses:
OVMS# log level debug simcom
Logging level for simcom set to
debug
OVMS# simcom cmd AT+COPS?
SIMCOM command has been sent.
D (164488782) simcom: tx mcmd ch=4
len=10 : AT+COPS?
D (164488792) simcom: rx line ch=4
len=23 : +COPS: 0,0,"congstar",2
D (164488802) simcom: rx line ch=4
len=2 : OK
Now let's see if we have 3G:
OVMS# simcom cmd AT+CPSI?
SIMCOM command has been sent.
D (164693462) simcom: tx mcmd ch=4
len=10 : AT+CPSI?
D (164693482) simcom: rx line ch=4
len=85 : +CPSI:
WCDMA,Online,262-01,0x16C3,7824927,WCDMA IMT
2000,454,10836,0,7.5,104,18,8,500
D (164693482) simcom: rx line ch=4
len=2 : OK
Yes. Well, no surprise, Telekom network :-).
The SIM5360 is supposed to automatically fall back
to 2G if 3G isn't available. On a quick browse
through the manual, I didn't find a command to force
2G, just one to lock to a specific 2G cell… you
could do that depending on your location, but maybe
you should first inspect your modem status now.
Regards,
Michael
Am 02.08.20 um 09:39
schrieb Chris van der Meijden:
Hi all
I'm trying to understand some
principals of the SIM connection methods of
OVMS.
Reason is that I recently moved from
"the big city" Munich to the very much rural
village Thalham. In Thalham we have so called
"lite" mobile transmitters. These transmitters
are installed, as far as I understood, to safe
money and to prepare the transition of the
providers to 4g / 5g. They are forcing the
frequencies towards the 4g band with those.
So these transmitters seem to offer
only 2g and 4g, but no more 3g (really ???).
I don't have any network connection
with the SIM in my OVMS here in Thalham. In the
next village Zolling I have connection. In
Zolling they don't have the "lite" transmitters,
but still have full 3g support. The antenna of
my OVMS is working well (-100 dBm to -70 dBm).
Now my questions ...
Does OVMS have a fallback on SIM5360
Europe to 2g (EDGE) if 3g is not available?
I also did some reading in the modem
documentation and tried to send some AT
commands. Goal is to try to force the SIM into
2g mode. I tried i.e.
simcom muxtx 2 AT+COPS?
to get some information from the
SIM, but I don't get an answer on that command
at all. No matter what channel I try. Am I
missing something there?
Thanx for input.
Regards
Chris
_______________________________________________
OvmsDev mailing list
OvmsDev@lists.openvehicles.com
http://lists.openvehicles.com/mailman/listinfo/ovmsdev
_______________________________________________
OvmsDev mailing list
OvmsDev@lists.openvehicles.com
http://lists.openvehicles.com/mailman/listinfo/ovmsdev
_______________________________________________
OvmsDev mailing list
OvmsDev@lists.openvehicles.com
http://lists.openvehicles.com/mailman/listinfo/ovmsdev
_______________________________________________
OvmsDev mailing list
OvmsDev@lists.openvehicles.com
http://lists.openvehicles.com/mailman/listinfo/ovmsdev
_______________________________________________
OvmsDev mailing list
OvmsDev@lists.openvehicles.com
http://lists.openvehicles.com/mailman/listinfo/ovmsdev
_______________________________________________
OvmsDev mailing list
OvmsDev@lists.openvehicles.com
http://lists.openvehicles.com/mailman/listinfo/ovmsdev
_______________________________________________
OvmsDev mailing list
OvmsDev@lists.openvehicles.com
http://lists.openvehicles.com/mailman/listinfo/ovmsdev