Unknown user at 01:28, 2 October 2022

2022-10-02T01:28:21Z

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	Sumber: https://en.wikipedia.org/wiki/Real-time_clock		Sumber: https://en.wikipedia.org/wiki/Real-time_clock

	~~A real~~-~~time clock~~ (RTC) ~~is an electronic device~~ (~~most often in the form of an~~ integrated circuit) ~~that measures the passage of time~~.		Real-Time Clock (RTC) adalah perangkat elektronik (paling sering dalam bentuk integrated circuit) yang mengukur perjalanan waktu.

	~~Although the term often refers to the devices in personal computers~~, ~~servers and~~ embedded ~~systems~~, ~~RTCs are present in almost any electronic device which needs to keep accurate time of day~~		Meskipun istilah ini sering mengacu pada perangkat di komputer pribadi, server, dan embedded system, RTC hadir di hampir semua perangkat elektronik yang perlu menjaga waktu yang akurat dalam sehari.

			Istilah real-time clock digunakan untuk menghindari kebingungan dengan jam perangkat keras biasa yang hanya merupakan sinyal yang mengatur elektronik digital, dan tidak menghitung waktu dalam satuan manusia. RTC tidak harus bingung dengan real-time computing, yang juga disingkat RTC tetapi tidak secara langsung berhubungan dengan time of day.

	~~The term real-time clock is used to avoid confusion with ordinary hardware clocks which are only signals that govern digital electronics~~, ~~and do not count time in human units.~~ RTC ~~should not be confused with real-time computing, which shares its three-letter acronym but does not directly relate to time of day.~~		Meskipun menjaga waktu dapat dilakukan tanpa RTC, menggunakan RTC memiliki manfaat:

	~~Purpose~~		* Konsumsi daya rendah (penting saat menjalankan dari daya alternatif)
	~~Although keeping time can be done without an~~ RTC,~~[1] using one has benefits:~~		* Membebaskan sistem utama untuk tugas-tugas penting waktu
			* Terkadang lebih akurat daripada metode lain
			* Penerima GPS dapat mempersingkat waktu mulainya dengan membandingkan waktu saat ini, menurut RTC-nya, dengan waktu terakhir ia memiliki sinyal yang valid. Jika sudah kurang dari beberapa jam, maka ephemeris sebelumnya masih bisa digunakan.

	~~Low power consumption[2]~~ (~~important when running from alternate power~~)		Beberapa motherboard dibuat tanpa real time clock. Real time clock dihilangkan karena keinginan untuk menghemat uang (seperti dalam arsitektur sistem Raspberry Pi) atau karena jam waktu nyata mungkin tidak diperlukan sama sekali (seperti dalam arsitektur sistem Arduino).
	~~Frees the main system for time-critical tasks~~
	~~Sometimes more accurate than other methods~~
	A GPS receiver can shorten its startup time by comparing the current time, according to its RTC, with the time at which it last had a valid signal.[3] If it has been less than a few hours, then the previous ephemeris is still usable.

	~~Some motherboards are made without real time clocks~~. The real time clock is omitted either out of the desire to save money (as in the Raspberry Pi system architecture) or because real time clocks may not be needed at all (as in the Arduino system architecture[4]).		RTC sering kali memiliki sumber daya alternatif, sehingga mereka dapat terus menjaga waktu saat sumber daya utama mati atau tidak tersedia. Sumber daya alternatif ini biasanya baterai lithium dalam sistem yang lebih tua, tetapi beberapa sistem yang lebih baru menggunakan superkapasitor, karena dapat diisi ulang dan dapat disolder. Sumber daya alternatif juga dapat memasok daya ke RAM yang didukung batere.

			==Timing==

	~~RTCs often have an alternate source of power~~, ~~so they can continue to keep time while the primary source of power is off or unavailable~~. ~~This alternate source of power is normally a lithium battery in older systems~~, ~~but some newer systems use a supercapacitor~~,~~[5][6] because they are rechargeable and can be soldered~~. ~~The alternate power source can also supply power to battery backed RAM~~.~~[7]~~		Kebanyakan RTC menggunakan osilator kristal,tetapi beberapa memiliki opsi untuk menggunakan frekuensi dari saluran listrik. Frekuensi kristal biasanya 32,768 kHz, frekuensi yang sama digunakan pada jam kuarsa dan jam tangan. Menjadi persis 215 siklus per detik, ini adalah tingkat yang nyaman untuk digunakan dengan simple binary counter circuit. Frekuensi rendah menghemat daya, namun tetap berada di atas jangkauan pendengaran manusia. Garpu tala kuarsa dari kristal ini tidak banyak berubah ukuran dari suhu, sehingga suhu tidak banyak mengubah frekuensinya.

	~~Timing~~		Beberapa RTC menggunakan resonator mikromekanis pada chip silikon RTC. Ini mengurangi ukuran dan biaya RTC dengan mengurangi jumlah suku cadangnya. Resonator mikromekanis jauh lebih sensitif terhadap suhu daripada resonator kuarsa. Jadi, ini mengkompensasi perubahan suhu menggunakan termometer elektronik dan logika elektronik.
	Most RTCs use a crystal oscillator,[8][9] but some have the option of using the power line frequency.[10] The crystal frequency is usually 32.768 kHz,[8] the same frequency used in quartz clocks and watches. ~~Being exactly 215 cycles per second, it is a convenient rate to use with simple binary counter circuits~~. ~~The low frequency saves power, while remaining above human hearing range~~. ~~The quartz tuning fork of these crystals does not change size much from temperature~~, ~~so temperature does not change its frequency much~~.

	~~Some RTCs use a micromechanical resonator on the silicon chip of the~~ RTC. ~~This reduces the size and cost of an RTC by reducing its parts count~~. ~~Micromechanical resonators are much more sensitive to temperature than quartz resonators~~. So, ~~these compensate for temperature changes using an electronic thermometer and electronic logic~~.~~[11]~~		Spesifikasi akurasi kristal RTC tipikal adalah dari ±100 hingga ±20 bagian per juta (8,6 hingga 1,7 detik per hari), tetapi IC RTC kompensasi suhu tersedia dengan akurasi kurang dari 5 bagian per juta. Secara praktis, ini cukup baik untuk melakukan navigasi bintang, tugas klasik sebuah kronometer. Pada tahun 2011, jam atom skala chip menjadi tersedia. Meskipun jauh lebih mahal dan haus daya (120 mW vs. <1 W), mereka menjaga waktu dalam 50 bagian per triliun (5×10^−11).

	Typical crystal RTC accuracy specifications are from ±100 to ±20 parts per million (8.6 to 1.7 seconds per day), but temperature-compensated RTC ICs are available accurate to less than 5 parts per million.[12][13] In practical terms, this is good enough to perform celestial navigation, the classic task of a chronometer. In 2011, chip-scale atomic clocks became available. Although vastly more expensive and power-hungry (120 mW vs. <1 μW), they keep time within 50 parts per trillion (5×10−11).[14]

	==Referensi==		==Referensi==

	* https://en.wikipedia.org/wiki/Real-time_clock		* https://en.wikipedia.org/wiki/Real-time_clock

Unknown user: Created page with "Sumber: https://en.wikipedia.org/wiki/Real-time_clock A real-time clock (RTC) is an electronic device (most often in the form of an integrated circuit) that measures the pass..."

2022-10-02T01:17:56Z

Created page with "Sumber: https://en.wikipedia.org/wiki/Real-time_clock A real-time clock (RTC) is an electronic device (most often in the form of an integrated circuit) that measures the pass..."

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Sumber: https://en.wikipedia.org/wiki/Real-time_clock

A real-time clock (RTC) is an electronic device (most often in the form of an integrated circuit) that measures the passage of time.

Although the term often refers to the devices in personal computers, servers and embedded systems, RTCs are present in almost any electronic device which needs to keep accurate time of day

The term real-time clock is used to avoid confusion with ordinary hardware clocks which are only signals that govern digital electronics, and do not count time in human units. RTC should not be confused with real-time computing, which shares its three-letter acronym but does not directly relate to time of day.

Purpose
Although keeping time can be done without an RTC,[1] using one has benefits:

Low power consumption[2] (important when running from alternate power)
Frees the main system for time-critical tasks
Sometimes more accurate than other methods
A GPS receiver can shorten its startup time by comparing the current time, according to its RTC, with the time at which it last had a valid signal.[3] If it has been less than a few hours, then the previous ephemeris is still usable.

Some motherboards are made without real time clocks. The real time clock is omitted either out of the desire to save money (as in the Raspberry Pi system architecture) or because real time clocks may not be needed at all (as in the Arduino system architecture[4]).

RTCs often have an alternate source of power, so they can continue to keep time while the primary source of power is off or unavailable. This alternate source of power is normally a lithium battery in older systems, but some newer systems use a supercapacitor,[5][6] because they are rechargeable and can be soldered. The alternate power source can also supply power to battery backed RAM.[7]

Timing
Most RTCs use a crystal oscillator,[8][9] but some have the option of using the power line frequency.[10] The crystal frequency is usually 32.768 kHz,[8] the same frequency used in quartz clocks and watches. Being exactly 215 cycles per second, it is a convenient rate to use with simple binary counter circuits. The low frequency saves power, while remaining above human hearing range. The quartz tuning fork of these crystals does not change size much from temperature, so temperature does not change its frequency much.

Some RTCs use a micromechanical resonator on the silicon chip of the RTC. This reduces the size and cost of an RTC by reducing its parts count. Micromechanical resonators are much more sensitive to temperature than quartz resonators. So, these compensate for temperature changes using an electronic thermometer and electronic logic.[11]

Typical crystal RTC accuracy specifications are from ±100 to ±20 parts per million (8.6 to 1.7 seconds per day), but temperature-compensated RTC ICs are available accurate to less than 5 parts per million.[12][13] In practical terms, this is good enough to perform celestial navigation, the classic task of a chronometer. In 2011, chip-scale atomic clocks became available. Although vastly more expensive and power-hungry (120 mW vs. <1 μW), they keep time within 50 parts per trillion (5×10−11).[14]

==Referensi==

* https://en.wikipedia.org/wiki/Real-time_clock

Arduino: RTC Definisi - Revision history

Unknown user at 01:28, 2 October 2022

Unknown user: Created page with "Sumber: https://en.wikipedia.org/wiki/Real-time_clock A real-time clock (RTC) is an electronic device (most often in the form of an integrated circuit) that measures the pass..."