"Back end support required" means that you need to connect to the server for data analysis in order to obtain positioning results;

"Proprietary back-end support" means that you may need to pay to obtain relevant data before the terminal equipment can locate.

In this article, let's talk about satellite positioning, which is most closely related to the Internet of things.

 

Among many satellite positioning systems, the most well-known is GPS (Global Positioning System). It was developed by the United States in 1958, put into use in 1964 and achieved global coverage in 1994.

GPS consists of 24 working stars and 4 standby stars. The satellite operates in six non synchronous orbits with an altitude of 20200 km at 55 degrees to each other. In this way, more than four GPS satellites can be observed anywhere and at any time in the world. GPS satellite sends navigation messages (system time, ephemeris, almanac, satellite clock correction parameters, navigation satellite health status, ionospheric delay parameters, etc.) to the earth. After receiving the data sent by the satellite, the GPS terminal can determine the current position through solution, and output the data in NMEA0183 grid and WGS-84 coordinate system.

Some readers may ask, what if the satellite breaks down, isn't GPS going to be inaccurate? In fact, this worry is superfluous. There are not only backup satellites in orbit, but also NASA will entrust space X to reissue and replace the satellites at the end of their life every year.

Of course, GPS is not the only satellite positioning system. Just because of the pioneering position of GPS, many people habitually call all satellite positioning systems "GPS".

After all, when GPS satellites are used, they are clamped down by the United States. GPS satellites are controlled by the U.S. military. They can freely adjust the positioning accuracy of a certain region (such as the Middle East), and even make the solution results of terminal equipment quite different. Moreover, GPS satellite is one-way broadcast, does not have two-way communication capability, and its function is slightly single.

In view of this, many countries are also building or have built satellite positioning systems. asBeidou in China, Galileo in Europe, GLONASS in Russia and irnss in IndiaWait.

At present, Beidou in China has commercial capacity. With the reference station, it can even provide customers with positioning services accurate to mm. At the same time, Beidou also makes up for the lack of GPS and has the ability of short message (necessary for donkey friends and HNA. It is by no means comparable to the base station of mobile phone, but the charge is very touching).

Since there are so many satellites in space and so many different satellite positioning systems, how can we know whether a certain area is covered by positioning satellites and which satellites are covered?For Android phones, please search for "GPS data" in the app store and install it. After opening it, you can see the positioning satellite currently in use：

Due to the differences of smartphone operating system, positioning chip, antenna and algorithm, not all satellite systems for positioning can be searched. Generally speaking, smart phones can only find and use parts (as shown in the figure, that is, GPS Beidou GLONASS QZSS, without Galileo and irnss).

       

Operating frequencies of different frequency bands of each navigation system

Navigation system	country	Frequency band			working frequency
GPS	U.S.A	L1			1575.42MHZ ± 1.023MHZ
		L2			1227.60MHZ ± 1.023MHZ
		L5			1176.45MHZ ± 1.023MHZ
GLONASS	Russia	L1			1602.5625MHZ ± 4MHZ
		L2			1246.4375MHZ ± 4MHZ
BD1	China	S			2491.75MHZ ± 4.08MHZ
		L			1615.68MHZ ± 4.08MHZ (left-handed circular polarization)
BD2		B1			1561.098MHZ ± 2.046MHZ
		B2			1207.520MHZ ± 2.046MHZ
		B3			1268.520MHZ ± 10.23MHZ
Galileo	Europe	L1			1575.420MHZ ± 1.023MHZ
		E5b			1207.140MHZ ± 1.023MHZ
		E5a			1176.450MHZ ± 1.023MHZ
		E6			1278.750MHz ± 1.023MHZ
QZSS	Japan	L1C		L1CD	1575.42 MHz
				L1CP
		L1-C/A
		L2C			1227.6 MHz
		L5	L5I		1176.45 MHz
			L5Q
		L1-SAIF			1575.42 MHz
		LEX			1278.75 MHz
IRNSS	India	L5			1176.45 MHz
		S			2492.028 MHz

     
       

Looking at the table, we can find that Japan is a "chicken thief" - L1 C / A, L1C, L2C and L5 signals are fully compatible with GPS satellite signals. At the same time, l1-saif can also provide high-precision positioning services to Japan; The frequency point of Lex signal coincides with E6 frequency point of European Galileo system. In other words, QZSS in Japan can be used as a supplement to GPS. In the future, QZSS can also supplement Galileo system when Galileo system officially provides services.

Next, enter the popular "you ask and I answer" link:

Q: Why is sometimes mobile positioning still very slow?

A: Signal problems, baseband problems, everything is possible. If you want to improve the positioning accuracy, the simplest way is to buy! One! New! Hands! Machine!

Q: I want to try Galileo. Do you have a supported mobile phone?

A: Huawei supports some models.

Q: Xiaomi 8 bangs are not good-looking. Look how beautiful vivo nex is. By the way, Xiaomi 8 said it was the first mobile phone in the world to support GPS dual band positioning (L1 and L5). It seems very awesome. Can it achieve centimeter level positioning?

A: No. Without the support of the reference station, the dual frequency is at most to reduce the error and is helpless for high-precision positioning. So, wash and sleep.

Q: How touching is Beidou's short message rate?

A: A dozen dollars a piece. You can go to a cat and a treasure to check the quotation.

As for voice communication, there are also maritime satellite phones available. The charges vary from more than ten yuan to dozens of yuan a minute in different countries; what? Do you want to use satellite Internet? How about $10 / 1m by volume? Is it affordable?

Q: Now that you have GPS, why rebuild the wheel?

A: Because L1 and L5 of GPS are civil codes, they are available to the public. At the time of the upgrading of the Sino US science and technology war, the chip has been held by the throat. How can the "privacy" of the positioning system be in the hands of others?

Q: Is GPS only useful on the surface?

A: No. Negative altitude (as long as there is a signal), in the air, or even outside the atmosphere. It should be noted that it cannot be used in objects with high density such as water and rocks.

For use outside the atmosphere, we should also pay attention to the impact of general relativity on the clock.

Q: In 007 tomorrow Empire, the villain used some awesome equipment, changed satellite parameters and hijacked a ship by some means. Is this possible?

A: This kind of thing has happened in the world.

Because the GPS signal has no authentication method, and the signal is very weak, it is very easy to be hijacked. For example, hackrf one can simulate and transmit GPS signals; Even let Dajiang UAV take off in the no fly zone.

Iran has also used similar technology to successfully capture American drones.

Q: How many satellites can we find at least to locate successfully?

A: Because of the principle of triangular positioning, at least three satellites can achieve accurate positioning; Specific requirements are as follows:

Number of satellites used	Can you locate	remarks
0	Unable to locate
one	Unable to locate	UTC time and date can be updated;
two	Unable to locate
three	It can realize 2D fix and output longitude and latitude	Altitude information cannot be output
four	3D fix	Correct altitude information can be output
>4 (multi frequency)	3D fix	Exportable pseudo range

                 
       

Q: Why do you know so much?

A: Probably because I'm taller than you.

Positioning article

Some people will ask, since there are many satellites in the sky, why do I only use a limited number of output results? This is because the small-size ceramic antenna used by the single chip microcomputer can only be compatible with two frequency bands (generally, the software also selects two), and can not be compatible with three frequency bands at the same time. Therefore, it is usually single choice GPS or Beidou; Or the combination of GPS Beidou and GPS GLONASS.

Some developers find that the code is correct, but the positioning module can't find the satellite and can't locate it?

In fact, troubleshooting this problem is both simple and complex. The reason why it is simple is that the only reason why we can't find the satellite is the signal problem. Complex because even if you know the cause, developers may feel helpless.

Signal problem, that is"Satellite → antenna → module → code → output"Something went wrong in one of the links. Here, combined with the "look, hear, ask and cut" method, we will break down the possible problems one by one.

first,Developers should keep in mind that at any time, there should be no foreign objects shielding the antenna in the space (such as trees, buildings and viaducts), and there are physical metal shells shielding the antenna (such as aluminum shells and iron shells). It shall be ensured that the test environment is open, unobstructed and the signal is good.

The reason why we have been emphasizing antenna, signal and no shielding is that the transmission power of the satellite is not large and the signal is very weak when it reaches the ground. This signal intensity is equivalent to the light emitted by a 25 watt bulb 16000 kilometers away. As another analogy, it is 1 billion times lower than the power received by the TV antenna.

If the signal is weak or no signal, it will be unable to locate or slow to locate. So, how to judge whether the positioning is slow or true due to signal problems; No signal? Observe the GGA, RMC and GSA output from the module:

GGA：

Format:

$--GGA,hhmmss. ss,llll. ll,a,yyyyy. yy,a,x,xx,x.x,x.x,M,x.x,M,x.x,xxxx*hh

Example:

$GPGGA,065545.789,2109.9551,N,12023.4047,E,1,9,0.85,18.1,M,8.0,M,,*5E

name	Sample	Company	describe
Message ID	$GPGGA		GGA # protocol header
UTC time	sixty-five thousand five hundred and forty-five point seven eight nine		hhmmss. sss
latitude	two thousand one hundred and nine point nine five five one		ddmm. mmmm
N/S	N		N = north, s = South
longitude	twelve thousand and twenty-three point four zero four seven		dddmm. mmmm
E/W	E		W = west, e = east
Positioning indication	one		0: not located 1: SPS} mode, effective positioning 2: Differential, SPS} mode, effective positioning 3: PPS} mode, effective positioning
Number of satellites	nine		Range 0 to 12
HDOP	zero point eight five		Horizontal accuracy
MSL amplitude	eighteen point one	rice
Company	M	rice
earth	-2.2	rice
Company	M		-
Differential time		second	Invalid when there is no DGPS}
Differential station ID
Checksum	*5E
			End of message

       

RMC：

Format:

$--RMC,hhmmss. ss,A,llll. ll,a,yyyyy. yy,a,x.x,x.x,xxxx,x.x,a*hh

example sentence:

$GPRMC,100646.000,A,3109.9704,N,12123.4219,E,0.257,335.62,291216,,,A*59

name	Sample	Company	describe
Message ID	$GPRMC		RMC} protocol header
UTC time	one hundred thousand six hundred and forty-six		hhmmss. sss
state	A		A = data valid; V = invalid data
latitude	two thousand one hundred and nine point nine seven zero four		ddmm. mmmm
N/S	N		N = north, s = South
longitude	eleven thousand one hundred and twenty-three point four two one nine		dddmm. mmmm
E/W	E		W = west, e = east
ground speed	zero point two five seven	Knot (section)
position	three hundred and thirty-five point six two	degree
date	two hundred and ninety-one thousand two hundred and sixteen		ddmmyy
Magnetic variable			-
Checksum	*59
			End of message

GSA：

Format:

$--GSA,a,a,x,x,x,x,x,x,x,x,x,x,x,x,x,x,x.x,x.x,x.x*hh

example sentence:

$GPGSA,A,3,10,24,12,32,25,21,15,20,31,,,,1.25,0.85,0.91*04

name	Sample	Company	describe
Message ID	$GPGSA		GSA} protocol header
Mode 1	A		M = manual (forced in 2D or 3D mode) A = Automatic
Mode 2	three		1: Invalid positioning 2: 2D} positioning 3: 3D} positioning
Satellite use	ten		Channel 1
Satellite use	twenty-four		Channel 2
Satellite use	twelve		Channel 3
Satellite use	thirty-two		Channel 4
Satellite use	twenty-five		Channel 5
Satellite use	twenty-one		Channel 6
Satellite use	fifteen		Channel 7
Satellite use	twenty		Channel 8
,,,	,,,	,,,
Satellite use			Channel 12
PDOP	one point two five		Position accuracy
HDOP	zero point eight five		Horizontal accuracy
VDOP	zero point nine one		Vertical accuracy
Checksum	*04
			End of message

• If UTC time in GGA is wrong,The positioning indication is 0, and the number of satellites is not 0； Or the UTC time and date of RMC are wrong; Number of satellites in GSANot 0However, if the carrier to noise ratio is very low, it may beSlow satellite search, slow positioning, poor signal；

  
  

• If UTC time in GGA is wrong,The positioning indication is 0, and the number of satellites is always 0； Or the UTC time and date of RMC are wrong; If the GSA has no valid output at all, it may beNo signal at all.

aboutSlow satellite search, slow positioning, poor signalThe antenna design shall be improved to ensure the installation and use state of the antenna facing upward; And there is no metal object around the antenna to block, and there is no RF interference; Large size ceramic antenna shall be selected as far as possible when space allows, and active antenna shall be used when necessary.

In the case of no signal at all, the probability is that the antenna design is wrong. For example, the active antenna is not powered on, the antenna model is used incorrectly (for example, the chip only supports GPS, the antenna only supports Beidou; the GSM antenna is used incorrectly to receive signals), etc.

Extended reading: design suggestions for GPS antenna of luat module

http://blog.sina.com.cn/s/blog_5b0121350102xy8v.html

Another common situation is that developers can't test indoors (including windows and windowsills). Because there is no satellite signal indoors, positioning cannot be realized.

If it is not convenient for developers to test outdoors, they can search "GPS} forwarding" in a treasure and buy relevant equipment. In this way, developers don't have to "take the trouble" to debug outdoors.

Next, let's enter the "you ask and I answer" link:

Q: Is there an antenna with small size and strong signal?

A: You can't have both fish and bear's paws. Only the most suitable, not the best.

Q: Where is NMEA-0183 format description?

A: Please http://www.openluat.com/ The GPS module of the product center is downloaded from the "Download Center".

Q: What is the relationship between GNSS and GPS?

A: Strictly speaking, GPS ∈ GNSS.

All satellite positioning systems can be called GNSS, and GPS is a subset of GNSS.

This is also reflected in the output, such as gngga, gpgga and bdgga, namely "hybrid positioning" (multi satellite system), "GPS positioning" and "Beidou Positioning".

Statement identifier:

identifier	meaning
BD	BDS, Beidou second generation satellite system
GP	GPS
GL	GLONASS
GA	Galileo
GN	GNSS, global navigation satellite system

Q: What is the difference between GGA, RMC and RSV?

A: All are required by NMEA-0183 standard. Their definitions are as follows:

identifier	meaning
GGA	Time, location, number of satellites and positioning mode
GSA	GPS} receiver operation mode, satellite used for positioning, DOP value, positioning status
GSV	Visible GPS satellite information, elevation, azimuth and signal-to-noise ratio
RMC	Time, date, location, speed
VTG	Ground speed information

  

Q: Is there any way to convert UTC time to local time?

A: On land, because many countries may span many time zones, but use the same time, they can only look up the table (such as UTC 8, Beijing time). If it is an ocean, the time zone is calculated based on longitude.

Q: Is there a mobile phone that can be used to test GPS and a powerful app?

A：Android：GPS Status； GPS Test ； GPS Data

iOS：GPS Test

Q: Why is the mobile phone positioning so fast and accurate, the positioning module so slow, and the error is still great?

A: Because the mobile phone is multi positioning (base station WiFi Bluetooth GPS AGPs historical data) at the expense of personal privacy, and the module only uses GPS antenna, it is slightly slower. However, after using "AGPs assisted positioning", second positioning can also be achieved.

Q: Why do you know so much?

A: Probably because I'm rich.

PS: so, how to use "AGPs assisted positioning"? Please pay attention to the following.

Second positioning

Why is the positioning speed not fast when the signal is excellent? Is there any way to achieve it"Second positioning"And? Of course, the answer is yes.

           
       

Under normal circumstances, after the positioning module is powered on, it searches the satellite through the antenna, analyzes the data transmitted by the satellite (navigation message), then internally generates the ephemeris, and then obtains the current accurate position (3D fix) through complex calculation. This process is called"Cold start"。 According to the signal strength and chip computing power, it usually takes tens of seconds to a few minutes.

In the process,Search for stars to generate ephemeris filesIt takes the longest.

However, some readers may ask, why sometimes the positioning module successfully locates in only a few seconds?There are two reasons: 1. Non "cold start" mode, i.e. "warm start" or "hot start";

2. AGPs assisted positioning is used.

So what is the difference between "cold start", "warm start" and "hot start"? Perhaps you will think that the "x startup" here is similar to the startup, standby (sleep) and restart of the computer? Actually, that's not the case. Since the space position of the satellite and the surface position of the terminal equipment are not fixed, the "x start" here is based on the last positioning time and displacement distance:

Start mode	explain	Autonomous second positioning*	Auxiliary second positioning*
cold boot	1. When used for the first time; 2. When the ephemeris information is lost due to battery depletion; 3. When moving more than 1000 km under shutdown.	×	√
Warm start	More than 2 hours and less than 4 hours from the last positioning time; No large distance displacement occurs.	√	√
Hot start	Less than 2 hours from the last positioning time; No large distance displacement occurs.	√	√

Autonomous second positioning: fast star searching and positioning can be realized according to the ephemeris saved in the module.

Auxiliary second positioning: use AGPs to realize fast satellite search and positioning.

In other words, under the conditions of "warm start" and "hot start", the positioning module can realize autonomous second positioning.

So, what is "AGPs assisted positioning"? In the traditional GPS positioning mode, the positioning module needs full band search to find available satellites, so it takes a long time. The "AGPs assisted positioning" method is to directly download the available satellite ephemeris data in the current area through the network and send it to the positioning module. The positioning module only searches for specific satellites, so as to improve the satellite search speed and reduce the power consumption of equipment.

For example: cold start is like a multiple-choice question. You have to calculate all the options before you can find the correct answer; The "AGPs assisted positioning" is like a cheater, eliminating many wrong answers, as long as a few can be calculated. So as to improve efficiency and accuracy.

However, there is no Holy Grail in the world, "AGPs assisted positioning" is not a panacea. Its application conditions still need to be relatively harsh:

· The satellite signal receiving conditions must be good, and at least 4 satellites can be observed (if possible,Active antenna is recommended）；

• Positioning chipAGPs assisted positioning must be supported；

• Must beaccuracyObtain the ephemeris data of the current region;

• In case of cold start, it is necessary to wait for the successful attachment of the communication chip and transmit the ephemeris data to the positioning module after receiving the ephemeris data;

• If it is warm start / hot start, it is also necessary to search the star again;

It can be seen that the second positioning can be realized only when the above conditions are met. If it is cold start} GPRS attachment to transmit ephemeris data, the waiting time is actually not short (it is even possible that the positioning module has 3D fix and GPRS has just attached successfully and sent ephemeris data).

Taking the air8xx series module of Shanghai Hezhou Communication Technology Co., Ltd. as an example, its AGPs auxiliary positioning basic process is as follows:

1、The device obtains the cell information of the current location from the cellular base station;

2、The device transmits the current cellular cell information to the AGPs location server in the network through the cellular network;

3、The APGs location server queries the currently available satellite information (including satellite frequency band, azimuth, elevation and other relevant information) in the area according to the current cell information, generates the corresponding ephemeris file and returns it to the equipment;

4、The communication module transmits the received ephemeris file to the positioning module through the serial port;

5、According to the available satellite information obtained from the ephemeris file, the positioning module can quickly find the currently available GPS satellites and search for satellites, which greatly improves the positioning time.

Next, let's enter the "you ask and I answer" link of universal celebration:

Q: My module has no GPS chip. Can I use "AGPs assisted positioning" to realize positioning?

A: Of course not. This question is equivalent to "can I run 100 miles without a supercharger and an engine". "AGPs assisted positioning" is only used to assist accelerated positioning, rather than an independent and available positioning service.

Q: Can "AGPs assisted positioning" improve positioning accuracy?

A: No, it can only speed up positioning. Positioning accuracy cannot be improved.

Q: How to judge whether AGPs is successfully written according to NMEA-0183?

A: Check whether the UTC time of GGA and RMC is corrected and whether the GSV data is generated;

             
       

GSV：

Format:

$--GSV,x,x,x,x,x,x,x,...* hh

example sentence:

$GPGSV,3,1,12,14,75,001,31,32,67,111,38,31,57,331,33,26,47,221,20*73

name	Sample	Company	describe
Message ID	$GPGSV		GSV} protocol header
Number of messages	three		1~3
Message number	one		1~3
Number of satellites	twelve
Satellite ID	fourteen		1~32
elevation	seventy-five	degree	0~90
azimuth	001	degree	0~359
Carrier noise ratio (C / no)	thirty-one	dBHz	0 ~ 99 (null without tracking)
Satellite ID	thirty-two		1~32
elevation	sixty-seven	degree	0~90
azimuth	one hundred and eleven	degree	0~359
Carrier noise ratio (C / no)	thirty-eight	dBHz	0 ~ 99 (null without tracking)
Satellite ID	thirty-one		1~32
elevation	fifty-seven	degree	0~90
azimuth	three hundred and thirty-one	degree	0~359
Carrier noise ratio (C / no)	thirty-three	dBHz	0 ~ 99 (null without tracking)
Satellite ID	twenty-six		1~32
elevation	forty-seven	degree	0~90
azimuth	two hundred and twenty-one	degree	0~359
Carrier noise ratio (C / no)	twenty	dBHz	0 ~ 99 (null without tracking)
Checksum	*73
			End of message

Q: Does the ephemeris file of "AGPs assisted positioning" consume much traffic?

A: Very few, just a few K.

Q: Do ephemeris files need to be updated regularly? What is the update frequency?

A: It needs to be analyzed according to its own situation. If it is cold start, do not close the positioning module and download the "AGPs auxiliary positioning" data (ephemeris file) once. During operation, the corresponding ephemeris file will be automatically generated in the positioning module without repeated downloading;

If it is started and closed irregularly, it is not necessary to update it within 4 hours of shutdown ("warm start" category); If the ephemeris saved in the module is invalid after more than 4 hours, the ephemeris file must be updated (downloaded again), otherwise it is the same as "cold start".

Q: Can you build your own AGPs ephemeris data server?

A: Yes. But it's more troublesome. It is recommended to use the interface provided by our company (please refer to the code of agps.lua in the routine).

Briefly describe how to build. First, download the navigation message data of BRDC on that day at NASA (take February 1, 2018 as an example):

ftp://cddis.gsfc.nasa.gov/pub/gps/data/daily/2018/brdc/brdc0320.18n.Z

(standby) ftp://igs.ensg.ign.fr/pub/igs/data/2018/032/brdc0320.18n.Z

Almanac of GPS satellite is included in the fourth and fifth subframes of navigation message, which can be regarded as a simplified subset of satellite ephemeris parameters. The server receives the request from the client, extracts the ephemeris of the current day from the navigation message, and then sends it to the client.

Extended reading: GPS satellite ephemeris and Almanac

https://blog.csdn.net/Csdn_Darry/article/details/72052686

Q: Taking gk9501 positioning chip as an example, how to send the data of "AGPs assisted positioning" to it?

A: Please refer to the relevant documents provided by the manufacturer and send the data to the positioning chip through the serial port in the specified format (please refer to the code of agps.lua in the routine).

Extended reading: test case of air series GPS module

http://blog.sina.com.cn/s/blog_5b0121350102xy8w.html

Q: Why do you know so much?

A: Probably because I'm handsome.

Mars coordinates (correction)

After suffering, we finally succeeded in positioning and obtaining the correct output. But how does it seem that the format is not quite right? The longitude and latitude are 4 and 5. Isn't that going to circle the earth several times?

In fact, this is a misunderstanding caused by the difference between the NMEA-0183 output format and the format we use every day. Let's take another look at the GGA format:

Format:

$--GGA,hhmmss. ss,llll. ll,a,yyyyy. yy,a,x,xx,x.x,x.x,M,x.x,M,x.x,xxxx*hh

Example:

$GPGGA,065545.789,2109.9551,N,12023.4047,E,1,9,0.85,18.1,M,8.0,M,,*5E

name	Sample	Company	describe
Message ID	$GPGGA		GGA # protocol header
UTC time	sixty-five thousand five hundred and forty-five point seven eight nine		hhmmss. sss
latitude	two thousand one hundred and nine point nine five five one		ddmm. mmmm
N/S	N		N = north, s = South
longitude	twelve thousand and twenty-three point four zero four seven		dddmm. mmmm
E/W	E		W = west, e = east
(omit part GGA)

Have you found the problem?

GGA output format: ddmm Mmmm (degrees minutes)

Daily use format: dd.dddd (degree)

So how to convert the data output by GGA into the format we use every day? Xueba will say at a glance that this problem is very simple, Balabala ~ ~ ~ as a learning slag, I am confused.

Cough, I'd better apply the formula directly.

The formula is as follows:

ddmm. Mmmm → move the decimal point forward by two digits → dd.mmmm → DD 0 (mmmm/60) = dd.dddddd

give an example:

12023.4047 → 120.234047 → 120 0. (234047÷60) = 120.390078

After such conversion, we can put the obtained values into the map software.

Everything seems beautiful, but... Until... You used Baidu map... Shit, lying slot... Why is the error so big? Deviation of hundreds of meters?

     
       

Clearly in the building, why does the map show me in the river? Why? Is there a problem with the positioning module? Or did mine write another bug? Or is the antenna faulty? Black question mark face.

 

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