JPH051185Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Technical Field) The present invention relates to a printing device that prints one frame or one field of a screen using a television signal or the like.

(Prior art) For example, there is a printing device that prints a video signal given from a digital television receiver as a source input signal as one frame of image displayed on the screen of the cathode ray tube (frame printing), or one field. A printing device that prints a minute image (field printing) is known.

By the way, the digital television receiver has 1
A memory (frame memory) for storing television signals for a frame or a memory (field memory) for storing television signals for one field is provided. When such a television receiver is equipped with a frame memory, the source input signal (video signal) applied to the printing device is a frame signal. Further, if a field memory is provided, the source input signal given to the printing device is a field signal.

By the way, if the printing device performs frame printing, the source input signal cannot be printed unless it is a frame signal, but the printing operation in such a printing device requires switching between odd and even fields in the frame signal. It needs to be done at 60Hz timing.

Furthermore, if the printing device is a field printing device, one field signal is printed. Therefore, in this case, it is necessary to determine which field the source input signal is for before printing.

However, conventional printing devices are fixed to either frame printing or field printing, so a printing device that can only perform frame printing cannot print if the source input signal is a field signal. Similarly, a printing device that can only print one field cannot print the other field signal.

An object of the present invention is to distinguish the field type whether the source input signal is a field signal or a frame signal, and to print image data of the field corresponding to the discrimination.

(Structure of the invention) In order to achieve the above-mentioned object, the present invention responds to the setting of printing conditions by sending a printing mode signal indicating whether the printing mode is frame printing mode or field printing mode, and a field indicating whether the printing field is the first field or the second field. a control means for outputting a type signal; a discrimination means for discriminating a field in response to a vertical synchronization signal and outputting a field discrimination signal corresponding to the field; a print mode signal and a field type signal from the control means; logic means for performing logical processing based on the field discrimination signal from the discrimination means and outputting a signal for printing the first field or the second field selected by the field type signal; and a printing control means for controlling printing based on the output.

(Embodiment) FIG. 1 is a schematic circuit diagram of the main parts of a printing device according to an embodiment of the present invention. In Fig. 1, 1 indicates the first printing condition, whether the printing mode is field printing or frame printing, and the second printing condition, whether the printing mode is printing the image data of the first field or printing the image data of the second field.
2 is a central control circuit (CPU) to which the first and second printing conditions are applied from the printing condition setting circuit 1 to its input section IN. This CPU2 has an output section OUT1
outputs a high-level field type signal S3 when printing an even field (first field), and a low-level field type signal S3' when printing an odd field (second field). The CPU 2 also outputs a high level print mode signal S2' during frame printing and a low level print mode signal S2 during field printing from the output section OUT2.

3 indicates whether the image data processed by the CPU 2 in response to the vertical synchronization signal V is of the first field or the second field.
In addition to determining whether the field is
The field discrimination circuit outputs a high level field discrimination signal S1' when determining that the field is a field, and outputs a low level field discrimination signal S1 when determining that it is a second field. 4 is a logic circuit consisting of an OR circuit OR, an exclusive logic NOR circuit EX1, an exclusive logic OR circuit EX2, and an AND circuit AD. This logic circuit 4 includes output parts OUT1 and OUT of the central control circuit 2.
2, and outputs S1, S1' from the field discrimination circuit 3,
Output S5 from output section OUT1 of print control circuit 5,
performs a logical operation in response to S5', and
Output S8 for input section IN of print control circuit 5,
S8' is output.

5 outputs the first or second signal in response to the outputs S8, S8' from the logic circuit 4 applied to its input section IN.
A print control circuit that controls printing of field image data; 6 is an output section OUT2 of the print control circuit 5;
This is a thermal printing head that prints image data on printing paper (not shown) in response to a control signal S9 from the printer.

(A) Next, in the case of field print mode, the operation for printing the image data of the first field is
This will be explained with reference to the figures. In addition to the case of first field printing, FIG. 2 also shows a time chart for second field printing for convenience. Second
FIG. 2a shows the vertical synchronizing signal V (low level portion) applied to the field discrimination circuit 3, and FIG. 2b shows the first and second field discrimination signals S1 and S1' output from the field discrimination circuit 3. The first field discrimination signal S1 is a low level signal, indicating that the field is the second field. The second field discrimination signal S1' is a high level signal, indicating that it is the first field.

FIG. 2c shows a signal S2 output from the output section OUT2 of the CPU 2, which is a field print mode signal S2 at a low level to indicate that the print mode is the field print mode.

FIG. 2 d shows the first and second field type signals S3, which are also output from the output section OUT1 of the CPU2.
The first field type signal S3' shown by a solid line in the figure is a high level signal indicating that the first field is printed. The second field type signal S3' indicated by a broken line in the figure is a low level signal indicating second field printing.

FIG. 2e shows the first and second outputs S4 and S4' from the OR circuit OR in the logic circuit 4. The high level first output S4 shown by a solid line corresponds to first field printing, and the low level second output S4' shown by a broken line corresponds to second field printing.

FIG. 2f shows the first and second outputs S5 and S5' from the print control circuit 5. The low level first output S5 shown by the solid line corresponds to the first field printing, and the high level first output S5 shown by the broken line corresponds to the first field printing.
5' corresponds to second field printing.

FIG. 2g shows the output S6 from the AND circuit AD. This output S6 is at a low level.

Figure 2 h is the output S of exclusive logic NOR circuit EX1.
7 is shown.

FIG. 2i shows the first and second outputs S8 and S8' from the exclusive OR circuit EX2. The first output S8 indicated by a solid line corresponds to first field printing, and the second output S8' indicated by a broken line corresponds to second field printing.

A setting signal S0 from the printing condition setting circuit 1 indicating that the printing mode is field printing and printing of image data of the first field is sent to the CPU 2.
is given to the input section IN. In response to the setting signal S0, the CPU 2 outputs a high-level field type signal S from its output section OUT1 as shown in FIG. 2d, which indicates that the print field type is the first field.
3, and outputs from its output section OUT2 a low-level print mode signal S2 as shown in FIG. 2c, which indicates that the print mode is field printing. Then, the OR circuit OR outputs a high level output S4 as shown in FIG. 2e. On the other hand, the output section OUT1 of the print control circuit 5 outputs the low level output S5 shown in FIG. 2f, which indicates first field printing. Therefore, the AND circuit
Since a low level signal is given to each of the two input terminals of the AD, the AND circuit
The AD outputs a low level output S6 as shown in FIG. 2g. Then, the field discrimination circuit 3 receives the low level field discrimination signal S1 which is determined to be the second field in periods T1 and T3, and the high level signal S1 which is determined to be the first field in the period T2. A field discrimination signal S1' is outputted respectively.
As a result, the exclusive logic NOR circuit EX1 outputs a signal S7 that changes as shown in FIG. 2h, and the exclusive logic OR circuit EX2 outputs a signal S8 as shown in the solid line in FIG. 2i. be done. A signal S8 from the exclusive OR circuit EX2 is applied to the input section IN of the print control circuit 5. Therefore,
The printing control circuit 5 performs the first field printing operation and drives the thermal printing head 6 only when the level of the signal S8 applied to its input section IN is high level.

In this way, the image data of the first field can be printed. Printing of the image data of the second field is performed in the same manner as described above.

(B) Next, the operation in the frame print mode will be explained with reference to FIG. Figures 3a to i correspond to Figures 2a to i, respectively. In this case as well, the printing of the image data of the first field will be explained, and the explanation of the printing of the image data of the second field will be omitted. A signal S0 indicating that the printing condition setting circuit 1 is in the frame printing mode and that the image data of the first field is to be printed is applied to the input section IN of the CPU 2. In response to this signal S0, the CPU 2 outputs the high level field type signal S3 shown in FIG. 3d from the output section OUT1, and outputs the high level print mode signal S3 shown in FIG. 3c from the output section OUT2. A signal S2' is output.

As a result, since the output S4 of the OR circuit OR and the output S6 of the AND circuit AD are the same as those in the case of FIG. 2, the output S4 from the exclusive OR circuit EX2 is
8 is the same as that in FIG. 2 as shown in FIG.
Printing control of the image data of the field is executed, and a control signal S9 is applied to the thermal printing head 6 to print the image data of the first field. Since the printing of the image data of the second field is the same as that of the first field, the explanation thereof will be omitted.

(Effects of the invention) As described above, according to the present invention, since it has the above-mentioned configuration, it is possible to discriminate between the first field and the second field in both the frame printing mode and the field printing mode. It has become possible to print image data corresponding to the determination.

[Brief explanation of drawings]

The drawings relate to an embodiment of the present invention; FIG. 1 is a circuit diagram of the embodiment, FIG. 2 is a time chart for the field print mode, and FIG. 3 is a time chart for the frame print mode as well. 1 is a print condition setting circuit, 2 is a CPU, 3 is a field discrimination circuit, 4 is a logic circuit, 5 is a print control circuit, and 6 is a thermal print head.

Claims (1)

[Claim for Utility Model Registration] A print mode signal indicating frame print mode or field print mode in response to print condition settings;
a control means for outputting a field type signal indicating whether the print field is a first field or a second field; and a control means for determining a field on the source input signal side in response to a vertical synchronization signal and outputting a field discrimination signal corresponding to the field. a first field or a second field selected by the field type signal by performing logical processing on the basis of the printing mode signal and the field type signal from the control means and the field discrimination signal from the determining means; 1. A printing device comprising: logic means for outputting a signal for printing; and print control means for controlling printing based on an output provided from the logic means.