CN102176110A - Analogue timer and setting and operating methods thereof - Google Patents
Analogue timer and setting and operating methods thereof Download PDFInfo
- Publication number
- CN102176110A CN102176110A CN2011100436248A CN201110043624A CN102176110A CN 102176110 A CN102176110 A CN 102176110A CN 2011100436248 A CN2011100436248 A CN 2011100436248A CN 201110043624 A CN201110043624 A CN 201110043624A CN 102176110 A CN102176110 A CN 102176110A
- Authority
- CN
- China
- Prior art keywords
- chip microcomputer
- resistance
- microcomputer controller
- corresponding voltage
- voltage value
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Images
Abstract
The invention discloses an analogue timer, and a setting method and an operating method thereof. The analogue timer comprises a singlechip microcomputer controller, at least one variable resistor, a memory cell and at least one output unit. The setting method comprises the following steps of: obtaining and storing an oscillation frequency ratio or a cycle ratio; changing a resistance value of the variable resistor; measuring and storing a corresponding voltage value; and repeating the changing step and the measurement step. The operating method comprises the following steps of: changing the resistance value of the variable resistor; measuring the corresponding voltage value, and calculating the resistance value of the variable resistor by utilizing a stored corresponding voltage value; calculating a time scale by utilizing the resistance value; calculating a numerical value of a counter according to the time scale and the stored oscillation frequency ratio of cycle ratio, and performing timing according to the numerical value; and outputting a timing finishing signal.
Description
Technical field
The present invention relates to a kind of analog timer and setting and method of operating, be particularly related to and a kind ofly replace RC oscillator and divider, set simple and easy quantification production and the accurate analog timer of timing and setting and method of operating to reach with the single-chip microcomputer controller.
Background technology
Referring to shown in Figure 1, analog timer 4 commonly used comprises an oscillator 40, a divider 41 and an output driver element 42, described oscillator 40 comprises an electric capacity 400, a variable resistor 401, described analog timer 4 utilizes the resistance value that changes described variable resistor 401 and the oscillation frequency that changes described oscillator 40, and then produces different timing girths.
The time constant that wherein said electric capacity 400 and described variable resistor 401 are constituted determines the oscillation frequency of described oscillator 40, through behind the described divider 41, when the counter of described divider 41 is zero, represent timing time to finish, can be by the signal of described output driver element 42 outputs one timing end.
The challenge of producing the maximum of analog timer 4 commonly used is to select suitable electric capacity 400 and variable resistor 401, producing the required timing of analog timer commonly used 4 at interval, need the different electric capacity 400 different variable resistor 401 of arranging in pairs or groups at different timing ranges.
Therefore, the many different electric capacity 400 and the stock of variable resistor 401 need prepare in production firm.All error can be arranged owing to indicate the electric capacity 400 or the variable resistor 401 of same numerical value, the electric capacity 400 that must from the electric capacity 400 of same sign by the gross, pick out suitable numerical value during production arrange in pairs or groups variable resistor 401, obtaining the reasonable time constant, thereby obtain timing more accurately at interval.
Yet, in order to reach needed degree of accuracy, even also will burn-on second or the 3rd building-out capacitor.Therefore make production procedure have not only slowly but also time-consuming shortcoming.In addition, if the not good words of described variable resistor 401 linearities, just when full scale, can obtain timing accurately at last, but at scale At All Other Times, be easy to produce no small error, therefore for the variable resistor 401 of the analog timer 4 that is applied to use always, the quality requirements of its linearity is relatively stricter, can all can obtain accurate timing result at all time scales.
In addition, if produce the various words of machine of analog timer 4 commonly used, prior art is produced the wiring board of a collection of no variable resistor 401 and electric capacity 400 usually earlier, up to receiving the variable resistor 401 and electric capacity 400 that it is suitable that order is just burn-on, thereby wasted many times, and then caused shortcomings such as cost height, production flexibility ratio be little.
Therefore, how to design one and set simple and easy quantification production, and can effectively proofread and correct variable-resistance resistance error, and the accurate analog timer of timing, just become be correlated with manufacturer and target that relevant research staff made joint efforts.
Summary of the invention
Not good in view of the production efficiency of analog timer commonly used, and for many shortcomings such as the electric capacity on timing basis and variable-resistance accuracy requirement height, first purpose of the present invention is to provide a kind of analog timer.
In order to reach above-mentioned purpose, analog timer of the present invention comprises:
One single-chip microcomputer controller, it produces an oscillation frequency or a fixed cycle signal, and has at least one corresponding voltage value and at least one is used for the counter of timing;
At least one variable resistor, itself and described single-chip microcomputer controller link, and described variable-resistance resistance value is corresponding to the corresponding voltage value of described single-chip microcomputer controller;
A storage unit, itself and described single-chip microcomputer controller link, and are used to store described corresponding voltage value; And
At least one output unit is used to export the signal that a timing finishes.
Second purpose of the present invention is to provide a kind of establishing method of analog timer.
In order to reach above-mentioned purpose, the establishing method of analog timer of the present invention uses above-mentioned analog timer, the described single-chip microcomputer controller of described analog timer further links with a setup unit, described setup unit stores a standard oscillation frequency or a normal period, and receive from the described oscillation frequency or the described fixed cycle signal of described single-chip microcomputer controller output, the establishing method of described analog timer comprises the following steps:
Obtain the oscillation frequency ratio or the periodic ratio of described fixed cycle signal and described normal period of the described oscillation frequency and the described standard oscillation frequency of described single-chip microcomputer controller, and store described oscillation frequency ratio or described periodic ratio;
Change described variable-resistance resistance value;
Measure described corresponding voltage value, and store described corresponding voltage value; And
Repeat described change step and measuring process repeatedly.
The 3rd purpose of the present invention is to provide a kind of method of operating of analog timer.
In order to reach above-mentioned purpose, the method for operating of analog timer of the present invention is used above-mentioned analog timer, and it comprises the following steps:
Change described variable-resistance resistance value;
Utilize described single-chip microcomputer controller to measure described corresponding voltage value, and utilize the corresponding voltage value that has stored to calculate described variable-resistance resistance value;
Utilize described variable-resistance resistance value, calculate the time scale that sets;
According to described time scale and the described oscillation frequency ratio or the described periodic ratio that have stored, calculate the numerical value of required counter, and carry out timing according to described numerical value; And
Export the signal that a timing finishes.
By above-mentioned device and method, can reach and set the target that simple and easy quantification is produced, and, more can reach the accurate purpose of timing because the present invention adopts the outside mode of adjusting to calibrate the oscillation error of single-chip microcomputer controller and the resistance error of the variable-resistance selected anglec of rotation.
Description of drawings
Fig. 1 is the structural representation of analog timer commonly used.
Fig. 2 is the structural representation of analog timer of the present invention.
Fig. 3 is the structural representation that an analog timer of the present invention and a setup unit link.
Fig. 4 is the process flow diagram of the establishing method of analog timer of the present invention.
Fig. 5 is the process flow diagram of the method for operating of analog timer of the present invention.
The main element symbol description
1: analog timer
10: the single-chip microcomputer controller
11: variable resistor
12: storage unit
13: output unit
2: the establishing method of analog timer
201: step 201
202: step 202
203: step 203
204: step 204
3: the method for operating of analog timer
301: step 301
302: step 302
303: step 303
304: step 304
305: step 305
4: analog timer commonly used
40: oscillator
400: electric capacity
401: variable resistor
41: divider
42: the output driver element
5: setup unit
Fn: standard oscillation frequency
Ft: oscillation frequency
R: oscillation frequency or periodic ratio
V
30: the corresponding voltage value of variable-resistance set angle 30 degree
V
90: the corresponding voltage value of variable-resistance set angle 90 degree
V
150: the corresponding voltage value of variable-resistance set angle 150 degree
V
210: the corresponding voltage value of variable-resistance set angle 210 degree
V
270: the corresponding voltage value of variable-resistance set angle 270 degree
V: corresponding voltage value
θ: variable-resistance set angle
T: timing girth
C: the numerical value of counter
N: during the every time sequential pulse (Clock) through N described single-chip microcomputer controller of the standard oscillation frequency of single-chip microcomputer controller, the numerical value of counter subtracts 1
Embodiment
For making those skilled in the art understand purpose of the present invention, existing conjunction with figs. is described in detail as follows preferred embodiment of the present invention.
Referring to shown in Figure 2, analog timer 1 of the present invention, it comprises:
One single-chip microcomputer controller 10, it produces an oscillation frequency or a fixed cycle signal, and has at least one corresponding voltage value and at least one is used for the counter of timing;
At least one variable resistor 11, itself and described single-chip microcomputer controller 10 link, and the resistance value of described variable resistor 11 is corresponding to the corresponding voltage value of described single-chip controller 10;
One storage unit 12, itself and described single-chip microcomputer controller 10 link, and are used to store described corresponding voltage value; And
At least one output unit 13 is used to export the signal that a timing finishes.
Wherein, described single-chip microcomputer controller 10 further comprises an analog-digital converter (not shown), and described analog-digital converter is used to read described corresponding voltage value; Described variable resistor 11 is rotary variable resistor, and the variation and the anglec of rotation of its resistance value are linear; Described storage unit 12 is a non-volatility memorizer, in preferred embodiment of the present invention, described non-volatility memorizer is Electrically Erasable Read Only Memory (EEPROM, Electrically Erasable Programmable Read Only Memory), flash memory (Flash Memory) or reluctance type storer (Magnetoresistive Random Access Memory), and described storage unit 12 is arranged at the inside or the outside of described single-chip microcomputer controller 10; Described output unit 13 is a relay, open collector (Open Collector), transistor-transistor logic circuit (Transistor-Transistor Logic) or a light emitting diode.
Referring to Fig. 3 and shown in Figure 4, the establishing method 2 of analog timer of the present invention, it uses above-mentioned analog timer 1, the described single-chip microcomputer controller 10 of described analog timer 1 further links with a setup unit 5, described setup unit 5 stores a standard oscillation frequency or a normal period, and receive from the described oscillation frequency or the described fixed cycle signal of described single-chip microcomputer controller 10 outputs, the establishing method 2 of described analog timer comprises the following steps:
Step 201: obtain the oscillation frequency ratio or the periodic ratio of described fixed cycle signal and described normal period of the described oscillation frequency and the described standard oscillation frequency of described single-chip microcomputer controller 10, and store described oscillation frequency ratio or described periodic ratio;
Step 202: the resistance value that changes described variable resistor 11;
Step 203: measure described corresponding voltage value, and store described corresponding voltage value; And
Step 204: repeating step 202 and step 203 many times.
Wherein, the anglec of rotation of described step 202 by changing described variable resistor 11 is to change the resistance value of described variable resistor 11.
Referring to Fig. 3 and shown in Figure 5, the method for operating 3 of analog timer of the present invention, it uses above-mentioned analog timer 1, and it comprises the following steps:
Step 301: the resistance value that changes described variable resistor 11;
Step 302: utilize described single-chip microcomputer controller 10 to measure described corresponding voltage value, and utilize the corresponding voltage value that has stored to calculate the resistance value of described variable resistor 11;
Step 303: utilize the resistance value of described variable resistor 11, calculate the time scale that sets;
Step 304: according to described time scale and the described oscillation frequency ratio or the described periodic ratio that have stored, calculate the numerical value of required counter, and carry out timing according to described numerical value; And
Step 305: export the signal that a timing finishes.
Wherein, described step 301 changes the resistance value of described variable resistor 11 by the anglec of rotation that changes described variable resistor 11; Described step 302 is carried out by described analog-digital converter.
Extremely shown in Figure 5 referring to Fig. 2, as is known to the person skilled in the art, the tentative standard oscillation frequency is Fn, and the oscillation frequency of described single-chip microcomputer controller 10 is Ft, described oscillation frequency ratio is R (R=Ft/Fn), and described oscillation frequency ratio is stored into described storage unit 12; Or suppose that be Tn described normal period, and the fixed cycle signal of described single-chip microcomputer controller 10 is Tt, described periodic ratio is R (R=Tn/Tt), and described periodic ratio is stored into described storage unit 12;
The described single-chip microcomputer controller 10 of described then setup unit 5 orders with a motor (or by artificial) the described variable resistor 11 of rotation to a certain angle to adjust the resistance value of described variable resistor 11, the described single-chip microcomputer controller 10 of described setup unit 5 orders reads described corresponding voltage value, and described corresponding voltage value is stored into described storage unit 12.
Then spend from the set angle 30 of described variable resistor 11, get once described corresponding voltage value every 60 degree, the pairing corresponding voltage value of angle of in regular turn that each is predetermined described variable resistor 11 deposits in the described storage unit 12, and the corresponding voltage value of set angle 30 degree of wherein said variable resistor 11 is V
30, the corresponding voltage value of set angle 90 degree of described variable resistor 11 is V
90, the corresponding voltage value of set angle 150 degree of described variable resistor 11 is V
150, the corresponding voltage value of set angle 210 degree of described variable resistor 11 is V
210, the corresponding voltage value of set angle 270 degree of described variable resistor 11 is V
270
At the machine parameter that will will set (as 30 seconds timer), write in the described storage unit 12 at last, promptly finish the program of setting by the parameter of described setup unit 5 with this machine.
During analog timer 1 that the user states in the use, earlier described variable resistor 11 is rotated to a certain angle to adjust the resistance value of described variable resistor 11, follow described single-chip microcomputer controller 10 and detect a described corresponding voltage value V, if described corresponding voltage value V is between above-mentioned V
30With V
90Between, then described single-chip microcomputer controller 10 can calculate the set angle θ of present described variable resistor 11 according to the interpolation method:
θ＝30°+(V-V
30)/(V
90-V
30)；
Set angle can be extrapolated the selected timing girth of user thus, and at described machine parameter (30 seconds timers), the numerical value C that described single-chip microcomputer controller 10 can calculate described counter is:
C＝T×(Fn×R/N)；
Wherein, when on behalf of the standard oscillation frequency of described single-chip microcomputer controller 10, N be the every time sequential pulse (Clock) through N described single-chip microcomputer controller 10 of Fn, the numerical value C of counter subtracted 1 and (supposes time sequential pulse=1/Fn).
When the numerical value C of described counter reduces to 0, the signal that described single-chip microcomputer controller 10 promptly orders described output unit 13 outputs one timing to finish, for instance, if described output unit 13 is a relay, the contact that the signal that then described timing finishes can be described relay becomes conducting (On) by open circuit (Off); If described output unit 13 is a light emitting diode, the signal that then described timing finishes can be the visible light that described light emitting diode sends.
In addition, the present invention is not limited to the function of single time timer, and analog timer 1 of the present invention can comprise plural variable resistor 11 and plural output unit 13, and reaches the function of timer of many time.
By above-mentioned device and method, because of the present invention replaces RC oscillator and divider with the single-chip microcomputer controller, thereby have and set the characteristic that simple and easy quantification is produced, and, more can reach the accurate purpose of timing because the present invention adopts the outside mode of adjusting to calibrate the oscillation error of single-chip microcomputer controller and the resistance error of the variable-resistance selected anglec of rotation.Moreover, its structure kenel be not under technical field technician institute can think easily and reach, so have novelty and progressive undoubtedly.
In sum, more than be preferred embodiment of the present invention only, be not to be used to limit protection scope of the present invention.Within the spirit and principles in the present invention all, any modification of being done, be equal to replacement, improvement etc., all should be included within protection scope of the present invention.
Claims (10)
1. analog timer, it comprises:
A single-chip microcomputer controller, it produces an oscillation frequency or a fixed cycle signal, and has at least one corresponding voltage value and at least one is used for the counter of timing;
At least one variable resistor, itself and described single-chip microcomputer controller link, and described variable-resistance resistance value is corresponding to the corresponding voltage value of described single-chip microcomputer controller;
A storage unit, itself and described single-chip microcomputer controller link, and are used to store described corresponding voltage value; And
At least one output unit is used to export the signal that a timing finishes.
2. analog timer as claimed in claim 1, wherein, described storage unit is a non-volatility memorizer, described non-volatility memorizer is electronics EPROM (Erasable Programmable Read Only Memory), flash memory or reluctance type storer.
3. analog timer as claimed in claim 1, wherein, described output unit is a relay, open collector, transistor-transistor logic circuit or a light emitting diode.
4. analog timer as claimed in claim 1, wherein, described single-chip microcomputer controller further comprises an analog-digital converter, described analog-digital converter is used to read described corresponding voltage value.
5. analog timer as claimed in claim 1, wherein, described storage unit is arranged at the inside or the outside of described single-chip microcomputer controller.
6. establishing method that uses the analog timer of analog timer as claimed in claim 1, the described single-chip microcomputer controller of described analog timer further links with a setup unit, described setup unit stores a standard oscillation frequency or a normal period, and receive from the described oscillation frequency or the described fixed cycle signal of described single-chip microcomputer controller output, the establishing method of described analog timer comprises the following steps:
Obtain the oscillation frequency ratio or the periodic ratio of described fixed cycle signal and described normal period of the described oscillation frequency and the described standard oscillation frequency of described single-chip microcomputer controller, and store described oscillation frequency ratio or described periodic ratio;
Change described variable-resistance resistance value;
Measure described corresponding voltage value, and store described corresponding voltage value; And
Repeat described change step and measuring process repeatedly.
7. the establishing method of analog timer as claimed in claim 6, wherein, described variable resistor is rotary variable resistor, and the step of the described variable-resistance resistance value of described change is for changing described variable-resistance resistance value by changing the described variable-resistance anglec of rotation.
8. method of operating of using the analog timer of analog timer as claimed in claim 6, it comprises the following steps:
Change described variable-resistance resistance value;
Utilize described single-chip microcomputer controller to measure described corresponding voltage value, and utilize the corresponding voltage value that has stored to calculate described variable-resistance resistance value;
Utilize described variable-resistance resistance value, calculate the time scale that sets;
According to described time scale and the described oscillation frequency ratio or the described periodic ratio that have stored, calculate the numerical value of required counter, and carry out timing according to described numerical value; And
Export the signal that a timing finishes.
9. the method for operating of analog timer as claimed in claim 8, wherein, described variable resistor is rotary variable resistor, and the step of the described variable-resistance resistance value of described change is for changing described variable-resistance resistance value by changing the described variable-resistance anglec of rotation.
10. the method for operating of analog timer as claimed in claim 8, wherein, described single-chip microcomputer controller further comprises an analog-digital converter, the step of the described corresponding voltage value of described measurement is carried out by described analog-digital converter.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 201110043624 CN102176110B (en) | 2011-02-22 | 2011-02-22 | Setting and operating methods for analogue timer |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 201110043624 CN102176110B (en) | 2011-02-22 | 2011-02-22 | Setting and operating methods for analogue timer |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN102176110A true CN102176110A (en) | 2011-09-07 |
| CN102176110B CN102176110B (en) | 2013-08-07 |
Family
ID=44519302
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN 201110043624 Expired - Fee Related CN102176110B (en) | 2011-02-22 | 2011-02-22 | Setting and operating methods for analogue timer |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN102176110B (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107015474A (en) * | 2015-09-23 | 2017-08-04 | 罗伯特·博世有限公司 | Time measurement device and method for asking for the period |
| CN112824923A (en) * | 2019-11-21 | 2021-05-21 | 芜湖美的厨卫电器制造有限公司 | Potentiometer resistance value interval updating method of electrical equipment and electrical equipment |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS54104279A (en) * | 1978-02-02 | 1979-08-16 | Mitsubishi Electric Corp | Timer |
| US4634985A (en) * | 1984-05-24 | 1987-01-06 | Fuji Electric Co., Ltd. | Time-interval signal generating apparatus |
| CN86106053A (en) * | 1986-09-06 | 1987-04-22 | 福建省机械科学研究院 | Multifunction programmable time controller |
| JPH05315964A (en) * | 1992-05-13 | 1993-11-26 | Omron Corp | Analog type set value input circuit |
| CN1566756A (en) * | 2003-06-30 | 2005-01-19 | 乐金电子(天津)电器有限公司 | Cooking time input device for microwave oven and input method thereof |
-
2011
- 2011-02-22 CN CN 201110043624 patent/CN102176110B/en not_active Expired - Fee Related
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS54104279A (en) * | 1978-02-02 | 1979-08-16 | Mitsubishi Electric Corp | Timer |
| US4634985A (en) * | 1984-05-24 | 1987-01-06 | Fuji Electric Co., Ltd. | Time-interval signal generating apparatus |
| CN86106053A (en) * | 1986-09-06 | 1987-04-22 | 福建省机械科学研究院 | Multifunction programmable time controller |
| JPH05315964A (en) * | 1992-05-13 | 1993-11-26 | Omron Corp | Analog type set value input circuit |
| CN1566756A (en) * | 2003-06-30 | 2005-01-19 | 乐金电子(天津)电器有限公司 | Cooking time input device for microwave oven and input method thereof |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107015474A (en) * | 2015-09-23 | 2017-08-04 | 罗伯特·博世有限公司 | Time measurement device and method for asking for the period |
| CN112824923A (en) * | 2019-11-21 | 2021-05-21 | 芜湖美的厨卫电器制造有限公司 | Potentiometer resistance value interval updating method of electrical equipment and electrical equipment |
Also Published As
| Publication number | Publication date |
|---|---|
| CN102176110B (en) | 2013-08-07 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN1551501B (en) | Calibration unit of calibrating resistance/capacitor filter circuit, filter device and method | |
| US7472028B2 (en) | Sensor or capacitance measuring with a microprocessor | |
| CN201548603U (en) | Digital oscilloscope with equivalent sampling functions | |
| RU2391677C1 (en) | Microcontroller metering transducer of capacitance and resistance into binary code | |
| CN102253286A (en) | Resistance/capacitance measuring method and device thereof | |
| CN103675461B (en) | Based on the resistance measurement method of adjustable current source | |
| CN106569544A (en) | Real time clock chip, and clock calibration method and apparatus | |
| CN104272119B (en) | Module and capacitance determining method | |
| CN103604523B (en) | A kind of thermocouple temperature display | |
| CN102662107A (en) | Micro control unit (MCU) built-in reference temperature compensation method based on system on chip (SOC) electric meter | |
| CN102176110B (en) | Setting and operating methods for analogue timer | |
| CN103604525A (en) | Thermal resistor temperature measuring instrument based on verification data | |
| CN104107032B (en) | Electric body-temperature is taken into account the school temperature method of this electronic thermometer | |
| CN108519521A (en) | Capacitance measurement system, method and apparatus | |
| CN102098051B (en) | Method and system for sampling high-frequency periodic signals | |
| CN103376162B (en) | Automatic temperature compensation method | |
| CN202166693U (en) | Resistance and capacitance measuring device | |
| CN101252357A (en) | Method and system for correcting parameter | |
| CN102507993B (en) | Burst signal generator with automatic initial phase calibration function | |
| JP6212256B2 (en) | AD conversion processor | |
| KR20080058285A (en) | Digital temperature and humidity sensor | |
| CN115373372A (en) | Calibration method of analog quantity measurement module | |
| RU2453854C1 (en) | Low-energy microcontroller-based measuring transmitter for variable resistance transducer | |
| CN101567693A (en) | Analog-to-digital converting apparatus with lower temperature dependence | |
| CN204902951U (en) | Digital capacitanc level meter based on TDC chip technology |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20130807 Termination date: 20200222 |
|
| CF01 | Termination of patent right due to non-payment of annual fee |