JPH01282917A - Electronic channel selection device - Google Patents

Abstract

PURPOSE:To rewrite number data for a number of times more than a guaranteed write of times by providing a means finding out an address in which a newest data signal is written and then writing a data signal including a flag signal to other address. CONSTITUTION:With a P position number given from a remote control reception section 3 or a key switch operation section 4, a band data 2-bit and a tuning voltage data 14-bit are read from an address of a nonvolatile memory 2' to control an electronic tuner 7 via a band changeover circuit 6 and a low pass filter 5 thereby selecting a channel. Then a flag signal representing the newest data signal is detected from a last position area in the nonvolatile memory 2' to find out an address storing the newest last position data. Then a flag signal 0001 is written to a high-order 4-bit and the position data P selected at present is written in the low-order 4-bit respectively in a hexadecimal number.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to an electronic channel selection device such as a television receiver that utilizes a nonvolatile memory.

BACKGROUND OF THE INVENTION In recent years, many electronic channel selection devices utilize microcomputers and non-volatile memory.

An example of the above-mentioned conventional electronic channel selection device will be described below with reference to the drawings.

FIG. 4 shows a block diagram of a conventional electronic channel selection device. In Fig. 4, 1 is a 1-chip microcomputer, 2 is a non-volatile memory, 3 is a remote control receiver that receives remote control signals, 4 is a key switch operation unit consisting of a plurality of key switches, and 5 is a low-pass filter (L ,
P, F ), 6 is a band switching circuit, 7 is an electronic tuner, and the band switching circuit 6 controlled by the microcomputer 1 controls VHF low hand (VL), VHF high band (VH), and U HF (U). One of the bands is selected, and a specific channel within the selected band is tuned by the tuning voltage provided by the low-pass filter 5, and an intermediate frequency signal is obtained from the electronic tuner 7.

The operation of the electronic channel selection device configured as described above will be explained below.

FIG. 5 is a schematic diagram showing the storage contents of the nonvolatile memory 2 in FIG. 4. The non-volatile memory 2 consists of 8 bits per address as shown in FIG.
Address 3 is used as a position data area.

Furthermore, the tuning data for one position consists of 2-bit band data and 14-bit tuning voltage data, and the tuning data for 12 positions is stored in order from position 1 to position 12 in the position data area. Suppose that

In FIG. 4, if the "1" position is selected by the remote control receiving section 3 or the key switch operation section 4, the microcomputer 1 receives the signal obtained from the remote control receiving section 3 or the pressed switch is in the position. Recognize that it is "1".

Next, the channel selection data at position "1" is read from addresses 0 and 1 of the nonvolatile memory 2. Among the data thus read out, band data 1 stored in the upper two bits of address 0 is output to the band switching circuit 6 to switch the band of the electronic tuner 7. Of the 16-bit tuning data that has been read out, 14 bits other than the band data are tuning voltage data, and the PWM (Pu I se W
The signal is pulse width modulated by the i dth fVlodulaton) circuit and output to the low-pass filter 5. The low-pass filter 5 smoothes this pulse-width modulated tuning voltage signal into a direct current, which is applied as a tuning voltage to the electronic tuner 7, and the channel indicated by position 1 is selected.

Furthermore, in order to remember the position currently selected,
As shown in FIG. 5, data “1” (16
decimal number). The lower 4 bits of the N address Q are called last position data, and are rewritten every time a position is selected by the remote control receiving section a or the key switch operation section 4.

Similarly, from the remote control receiving section 3 or the key switch section 4,
When the position number PJ is given, the microcomputer 1 selects ((P-1)X2) in the non-volatile memory 2.
Read 2 bits of band data and 14 bits of tuning voltage data from address and address ((P-1)X2+1),
Tuning is performed by controlling an electronic tuner 7 via a band switching circuit 6 and a low-pass filter 5. Furthermore, the last
Number rPJ in hexadecimal as position data, N
By writing to the lower 4 bits of the address, the series of channel selection operations is completed.

In the electronic channel selection device that operates as described above, the nonvolatile memory 2 retains its stored contents even when the power is turned off, and the last position data also remains stored.

Therefore, the next time the power is turned on, the microcomputer 1 first reads the last position data rPJ at address N, and then reads the last position data rPJ at address ((P-1)X2) and ((P-
1) By reading out the band data and tuning voltage data stored at address X2+1), the receiving channel before the power is turned off can be received. This will be referred to as last position memory.

Problems to be Solved by the Invention However, in the above configuration, in order to memorize the last position, NMOS (Metal
N1tride Oxide 5ernlconduo
(tor)) A non-volatile memory that guarantees 100,000 writes per address is required, such as memory.

However, due to recent advances in semiconductor technology, one-chip microcomputers with built-in EEFROMs have been developed, but the number of writes to EEFROMs is currently guaranteed to be only 10,000 times, and in order to memorize the last position, had the problem that the number of times of writing was insufficient.

In view of the above-mentioned problems, the present invention provides an electronic channel selection device that can store the last position more times than the guaranteed number of writes by using a nonvolatile memory with a small number of guaranteed writes. It is.

Means for Solving the Problems In order to solve the above problems, the electronic channel selection device of the present invention includes: a nonvolatile memory having a plurality of addresses; a means for reading a data signal from any address of the nonvolatile memory;
means for writing a data signal to any address of the nonvolatile memory, the data signal to be written includes a flag signal indicating that it is the latest write data signal, and the data signal is written to the nonvolatile memory. In the process of changing, an area with multiple addresses is secured in the non-volatile memory, first the address where the flag signal is written is found within the area, and then the flag is written to another address within the area. This is characterized in that data signals including signals are written.

Effect The present invention has the above-mentioned configuration, so that the last position
Since data is sequentially written to multiple addresses, the number of writes per address is reduced, and by using non-volatile memory with a small number of guaranteed writes, the last position can be written more times than the guaranteed number of writes. Memory becomes possible.

Embodiment Hereinafter, an electronic channel selection device according to an embodiment of the present invention will be described with reference to the drawings. FIG. 1 shows a block diagram of a channel selection device in one embodiment of the present invention.

In FIG. 1, 1 is a microcomputer, and 2' is a nonvolatile memory based on EEPROof/1 built into the microcomputer 1. In FIG. In addition, 3 is a remote control receiving section,
4 is a key switch operating section, 5 is a low-pass filter, 6 is a band switching circuit, and 7 is an electronic tuner, which performs the same operation as shown in FIG.

The operation of the electronic channel selection device configured as described above will be explained below with reference to FIGS. 2 and 3.

Here, FIG. 2 is a schematic diagram showing the storage contents of the nonvolatile memory 2', and FIG. 3 is an operation flow when the microcomputer 1 performs a channel selection operation.

rPJ from the remote control receiving section 3 or key switch operation section 4
When the microcomputer 1 is given the position number ((p-1)X2) of the nonvolatile memory 2'
2 bits of band data and 14 bits of tuning voltage data are read from the address and ((p-1) Next, the last position is stored. First, as shown in FIG. 2, the last position area (n
The address where the latest last position data is stored is found by detecting a flag signal indicating that it is the latest data signal. The procedure for finding this address is shown in Figure 3 (al). As shown in Figure 3 (a), data is read from address n, which is the first address in the last position area, and the upper 4 bits, which are flag signals, are read out. Determine whether all are rOJ. If rOJ, proceed to the next address sequentially and find an address (n+R) where the flag signal is not 0.
The lower four bits of the address (n+R) are the latest last position data. In this way, after finding the (n+R) address that stores the latest last position data, the upper 4 bits of the (n+R) address are all rewritten to 0, as shown in FIG. 3(b). If (n+R) is the last address of the last position area (n + rn-1), then the first address i of the last position area is used, and if not (n+R+1), the latest last position data is The address to be stored, with 0001 in the upper 4 bits.
The flag signal , and the currently selected position data rPJ are written in hexadecimal into the lower 4 bits.

Also, when the power is turned off and then turned on again, the microcomputer 1 finds the latest last position data by performing the operations shown in Figure 3 (-), and then performs the operations as described above. By reading band data and tuning voltage data from the address indicated by the last position, the channel before the power is turned off is selected.

As described above, according to this embodiment, when writing last position data to an area having m addresses from address n to address (n+m-1) in nonvolatile memory, first the latest position data is written. By finding the address from the flag signal indicating that it is the last position data, erasing the flag signal at that address, and writing the flag signal indicating that the data is the latest data and the last position signal to the next address. , the number of writes per address is 2/rn, and the last position can be stored more times than the guaranteed number of writes.

In the first embodiment, the flag signal is 0001, but the flag signal may be any data signal as long as it can be distinguished as the latest data.

Effects of the Invention As described above, according to the present invention, there is provided a non-volatile memory having a plurality of addresses, a means for reading a data signal from any address of the non-volatile memory, and a means for reading a data signal from any address of the non-volatile memory. means for writing a data signal;
The data signal to be written includes a flag signal indicating that it is the latest write data signal, and in the process of rewriting the data signal to the nonvolatile memory, the flag signal is first detected and the latest data signal is written. By providing a procedure for finding the address where the data signal is and then writing the data signal including the flag signal to another address, the data signal can be rewritten more times than the guaranteed number of times of writing.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of an electronic channel selection device according to an embodiment of the present invention, FIG. 2 is a schematic diagram of the nonvolatile memory used in FIG. 1, and FIG. 3 is an operation flow showing the operation of the embodiment. 4 is a block diagram of a conventional electronic channel selection device, and FIG. 5 is a schematic diagram of a nonvolatile memory used in FIG. 4. 1...Microcomputer, 2'...
・Non-volatile memory, 3...Remote control receiver, 4
...Key switch operation section, 7...Electronic tuner. Name of agent: Patent attorney Toshio Nakao and 1 other person No. 1
Figure 2 Figure 3 (eλ (b) Figure 4

Claims (1)

[Claims] A data signal to be written, comprising a non-volatile memory having a plurality of addresses, means for reading a data signal from any address of the non-volatile memory, and means for writing a data signal to any address of the non-volatile memory. is provided with a flag signal indicating that it is the latest write data signal, and in the process of rewriting the data signal to the nonvolatile memory, the flag signal is first detected and the address where the latest data signal is written is detected. An electronic channel selection device characterized in that it finds the flag signal and then writes a data signal including the flag signal to another address.