# RTCM3 support **URL:** \ **Category:** Skydel Discussion\ **Created:** [January 10, 2024, 12:43pm UTC](https://learn.safran-navigation-timing.com/t/rtcm3-support/1196 "2024-01-10T12:43:49Z")\ **Posts on this page:** 6\ **Page:** 1
**Author:** ![mac21](https://avatars.discourse-cdn.com/v4/letter/m/6a8cbe/32.png) [@mac21](https://learn.safran-navigation-timing.com/u/mac21)\ **Post date:** [January 10, 2024, 12:43pm UTC](https://learn.safran-navigation-timing.com/t/rtcm3-support/1196/1 "2024-01-10T12:43:49Z")
I am using Skydel GSG-7 for GNSS simulation.As i can see in the receiver section skydel can parse specific NMEA 0183 v4.1 sentences. My question is can it also parse RTCM3 data and can it also decode MSM7 messages? ---
**Author:** ![mathieu.favreau](https://avatars.discourse-cdn.com/v4/letter/m/eb8c5e/32.png) [@mathieu.favreau](https://learn.safran-navigation-timing.com/u/mathieu.favreau)\ **Post date:** [January 10, 2024, 8:16pm UTC](https://learn.safran-navigation-timing.com/t/rtcm3-support/1196/2 "2024-01-10T20:16:24Z")
Hi @mac21, The Receiver tab in Skydel only parses NMEA sentences, it’s only used to update Skydel’s User Interfaces. It is used for: - the PVT information in the Receiver tab - the satellite’s CN/0 in the Constellations tab - updating the Sky View with the satellites position in the Constellations tab - show the deviation between the simulated position and the receiver’s position in the Deviation tab Can you specify what exactly you would like Skydel to do with the RTCM3 data? Regards, Mathieu ---
**Author:** ![mac21](https://avatars.discourse-cdn.com/v4/letter/m/6a8cbe/32.png) [@mac21](https://learn.safran-navigation-timing.com/u/mac21)\ **Post date:** [January 11, 2024, 9:26am UTC](https://learn.safran-navigation-timing.com/t/rtcm3-support/1196/3 "2024-01-11T09:26:35Z")
ZF Confidential Hi Mathieu, Thank you for the detailed answer. I want skydel to parse RTCM3 data so that we can see the deviation between simulated and receivers position. This is the requirement from our project. But as I can understand from your answer it can only parse NMEA sentences. Do you have a workaround for my question? Regards, Mahesh. ![~WRD0001.jpg](https://canada1.discourse-cdn.com/flex030/uploads/orolia/original/1X/52d5f1c08649212fe6768d2cacdcf8df711810d9.jpeg) ---
**Author:** ![mathieu.favreau](https://avatars.discourse-cdn.com/v4/letter/m/eb8c5e/32.png) [@mathieu.favreau](https://learn.safran-navigation-timing.com/u/mathieu.favreau)\ **Post date:** [January 16, 2024, 8:36pm UTC](https://learn.safran-navigation-timing.com/t/rtcm3-support/1196/4 "2024-01-16T20:36:09Z")
Hi @mac21, You can already see the deviation between the simulated and receiver positions in the Deviation tab once you connected your receiver to Skydel. Skydel will compare the simulated position to the position found in the NMEA data sent by the receiver. I am unsure why the RTCM sentences would be required for this, could you explain in more details? Regards, Mathieu ---
**Author:** ![mac21](https://avatars.discourse-cdn.com/v4/letter/m/6a8cbe/32.png) [@mac21](https://learn.safran-navigation-timing.com/u/mac21)\ **Post date:** [January 29, 2024, 11:03am UTC](https://learn.safran-navigation-timing.com/t/rtcm3-support/1196/5 "2024-01-29T11:03:18Z")
Hi @mathieu.favreau Okay understood. Can you please share the details about how skydel parses NMEA streams. If possible,can i get the codebase of NMEA parsing? The reason i am asking this is I am currently creating custom NMEA senteces in CAPL script and will send it via seria port to GSG7. So for this purpose i need the information about NMEA parsing. ---
**Author:** ![mathieu.favreau](https://avatars.discourse-cdn.com/v4/letter/m/eb8c5e/32.png) [@mathieu.favreau](https://learn.safran-navigation-timing.com/u/mathieu.favreau)\ **Post date:** [January 29, 2024, 6:57pm UTC](https://learn.safran-navigation-timing.com/t/rtcm3-support/1196/6 "2024-01-29T18:57:09Z")
Hi @mac21, We support NMEA 0183 up to version 4.10, the sentences required by Skydel to compute the Deviation are RMC and GGA. I sadly can’t share the code, nor the spec since you have to buy it to have access to it. You can get more information about the standard from Wikipedia: > **[NMEA 0183](https://en.wikipedia.org/wiki/NMEA_0183)** > > NMEA 0183 is a combined electrical and data specification for communication between marine electronics such as echo sounder, sonars, anemometer, gyrocompass, autopilot, GPS receivers and many other types of instruments. It has been defined and is controlled by the National Marine Electronics Association (NMEA). It replaces the earlier NMEA 0180 and NMEA 0182 standards. In leisure marine applications it is slowly being phased out in favor of the newer NMEA 2000 standard, though NMEA 0183 The elec... Regards, Mathieu