JPH0461778B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention prints a series of characters, numbers, calculation symbols, etc. selected by operating each key on a keyboard, and also prints a series of characters, numbers, symbols for calculation, etc. The present invention relates to an electronic typewriter with an arithmetic function capable of processing numerical data inputted using numerical keys using an arithmetic expression specified using a calculation symbol (hereinafter referred to as an operation symbol) key and printing the result of the operation.

[Prior art]

This type of electronic typewriter with arithmetic functions is described in Utility Model Application No. 145947/1983, which was previously filed by the applicant of the present invention. However, the electronic typewriter described above, after inputting a sentence ending with a period,
In arithmetic processing in which an arithmetic expression is entered after a line break is performed by a carriage return, the first numeric data in the arithmetic expression is assumed to have a decimal point at the beginning. In other words, the period input just before a line feed due to a carriage return is treated as a decimal point, and calculations are performed on the assumption that it follows the first numeric data on the next line. For example, after inputting the English text "This is a pen." and performing a carriage return, inputting the arithmetic expression "2+3" and executing the arithmetic processing resulted in a result of 3.2. As is well known, the correct result of the arithmetic expression "2+3" is 5, but this is because during arithmetic processing, the first numerical data "2" in the arithmetic expression "2+3" is treated as the period entered just before the line break, which is considered a decimal point. This is an error that occurred because it was recognized as 0.2.

As mentioned above, in conventional electronic typewriters with arithmetic functions, the period indicating the end of a sentence entered immediately before a carriage return line feed is calculated as the decimal point of the numerical data of the arithmetic expression entered at the beginning of the next line. There were cases where accurate calculation results could not be obtained because of the processing.

[Purpose of the invention]

The purpose of the present invention is to eliminate the above-mentioned conventional difficulties, and to recognize that the period entered by the key to indicate the end of a sentence immediately before a line break due to a carriage return and the arithmetic expression entered on the next line are not related to each other. An object of the present invention is to provide an electronic typewriter with an arithmetic function that performs arithmetic processing.

[Configuration of Example]

Hereinafter, the configuration of an embodiment of the present invention will be described with reference to FIGS. 1 and 2.

In FIGS. 1 and 2, a keyboard 1 is arranged with character keys, numeric keys, arithmetic symbol keys, symbol keys such as a period key that also serves as a decimal point, and function keys, and data input from the keyboard 1 is stored. A RAM (readable and writable memory) 4 that serves as a working device such as a display buffer 2 and a decimal point flag 3, and a liquid crystal display device (hereinafter referred to as
An LCD controller 6 controls an LCD (referred to as an LCD) 5, and drives a printing device 10 which performs printing by moving a carriage 8 equipped with a print head 7 and feeding paper 9 according to data entered from a keyboard 1. Printing device drive unit 11 that controls
and a ROM (read-only memory) 12 in which programs for executing various processes are stored are connected to a central processing unit (hereinafter referred to as CPU) 13.

[Operation of the embodiment]

The operation of the above configuration will now be described with reference to FIGS. 1 to 3.

In FIG. 3, first, in step 21, key input from the keyboard 1 is scanned. Here, if there is no key input, scanning continues; if any key input is received, the process advances to the next step 22. Here, the key input data is input to the display buffer 2 for the LCD 5 and temporarily stored. Next, the process proceeds to step 23, where it is determined whether the key input data is a period. Here, if the key input data is a period, proceed to the next step.
Proceed to step 24, set decimal point flag 3, and then go to step 21 again. On the other hand, if the key input data is not a period in step 23, the process proceeds to step 25, where it is determined whether the key input data is a carriage return. Here, if the key input data is not a carriage return, proceed to step 26 and perform processing according to the key input data.On the other hand, if the key input data is a carriage return, proceed to the next step 27. Proceed to. Here, it is determined whether or not the key input data immediately before the carriage return is a period. If it is not a period, the process goes to step 21 again, and if it is a period, the process goes to the next step 28. Here, it is determined whether the key input data immediately before the period is a number or arithmetic symbol. If it is a number or arithmetic symbol, go to step 21 again; if it is not a number or arithmetic symbol, go to the next step. Proceed to 29. Here, the decimal point flag 3 is cleared and the process proceeds to the next step 30, and after performing a carriage return, the process proceeds to step 21 again.

In addition, the process of arithmetic processing is carried out by the present applicant in advance, except for determining whether or not to add a decimal point to the first numerical data head of the arithmetic expression and perform the calculation based on the state of the decimal point flag 3 in RAM4. The control circuit 11, the arithmetic circuit 14, and the register 14a of the embodiment in Utility Model Application No. 56-145947 are replaced by the CPU 13 of this embodiment, respectively. , ROM12 and RAM4, it can be easily understood.

〔Effect of the invention〕

As described in detail above, the electronic typewriter with arithmetic functions according to the present invention can prevent a period keyed in to indicate the end of a sentence immediately before a carriage return to a new line from being mistakenly recognized as a decimal point. Accurate calculation processing becomes possible.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing one embodiment of the present invention;
FIG. 2 is a schematic perspective view thereof, and FIG. 3 is a flowchart thereof. In the figure, 1 is the keyboard, 2 is the display buffer, and 3 is the keyboard.
is the decimal point flag, 4 is the RAM, 10 is the printing device,
12 is a ROM, and 13 is a central processing unit.

Claims (1)

[Scope of Claims] 1. A keyboard that is arranged with character keys, numeric keys, a period that also serves as a decimal point, symbol keys for calculations such as addition, subtraction, multiplication, and division, and function keys such as carriage return, and a keyboard that corresponds to input from the keyboard. In an electronic typewriter having a printing device for printing, paper feeding, and carriage feeding, there is provided a control means for calculating a calculation formula inputted from a keyboard and printing the calculation result together with the calculation formula, and the control means is configured as described above. When calculating a calculation formula, if a period key is input immediately before the carriage return key, only if the key input immediately before the period key was a numeric key, the period key command is treated as a decimal point and the calculation is processed. An electronic typewriter with arithmetic functions.