JPS6063657A - Electronic calculator - Google Patents

Abstract

PURPOSE:To display a calculation mode state without providing any mode state displaying symbol by displaying a set calculation mode state only by display elements of Japanese segments. CONSTITUTION:An arithmetic processing unit CPU performs key input control, display control, calculation, etc. This arithmetic processing part CPU includes a clock signal generation part CG, program memory ROM, program counter PC, stack registers STACK1 and STACK2, decoder DECODER, data pointer DP, memory RAM, accumulator A, logical arithmetic unit ALU, etc., and the calcula- tion result is display at a display part DIPS. A set calculation mode is displayed only by display elements of Japanese segments.

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field The present invention relates to an electronic desktop calculator (hereinafter referred to as a "calculator").

<Prior art> In the past, in a calculator with an electronic mode switch, in order to display the set calculation mode state, it was necessary to provide a dedicated mode state display symbol or use a display element capable of displaying characters. Met.

<Object of the Invention> The present invention makes it possible to display the calculation mode state without providing a mode state display symbol even though a Japanese character segment display element is used, thereby making it possible to easily realize an electronic mode switch. It is.

<Embodiment> FIG. 1 is a schematic diagram of a system implementing the present invention, and each block in the figure is as shown below.

CPU: An arithmetic processing unit that performs key manual control, display control'', calculations, etc., and is composed of the following blocks.

CG: CPU clock signal φ generation unit ROM Niprogram memory PC Niprogram counter 5 TACKI Ni program register 5 TACK2: DECODER Decoder that decodes the command output from the Ni program memory and generates the control signal DP= Data pointer πAM: Memory A near-accumulator for storing calculation registers, flags, etc. ALU: Logical operation unit PORTI: Input port PORT2: Output boat KEY: Key human power section DISP: Display section Figures 2 and 3 show the following: They are a detailed diagram of a display section and a detailed diagram of a key input section of the system schematic diagram of FIG. 1, respectively.

[TAB J, r i J, r
5/4J.

Each "1" symbol is printed on the filter.

The operation will be explained below by way of example.

■ In the initial state, "0." is displayed as shown in Figure 4.

■Takumi ■Down E When the key is operated, the initial setting of the calculation mode (TA, B=2.Rounding off) is displayed as shown in FIG.

■ Request] By operating the keys, TAB, f,
By operating the 3K setting and the 5 keys, the round-up mode is set and the display is displayed as shown in FIG.

■4■2nd field If you operate the key, the state will change to ■ again.
Able to perform calculations. In other words, unless changed from now on, TAB=3. Often used in round-up mode.

FIG. 7 is a flowchart 1 for explaining the operation.

In Figure 7, ■ First, the initial state is set (n+, n2).

a) Calculation mode is set to TAB=2.5/4 (rounded off) (n,).

b) The MD flag is set and the calculation result is displayed (n2).

■ Preparations for display are made (n3 to IN+)
.

a) If the MD flag has been reset, the contents of the X register in which the calculation results are stored are displayed (n3).

b) If the MD flag is set, prepare to display the calculation mode. First, save the calculation result in the X register to the W register, and all digits in the X register are "15".
(n4 + ns). Next, enter the stored TAB setting value into the 10th digit of the X register (n
6).

Furthermore, refer to the settings for rounding processing, and
~Insert “11” in any of the 8th digits (n7no)
.

■ The contents of the X register are displayed until key power is generated (n12 to n18).

a) 't', set digit counter 1 to '1' (n+2
).

b) After outputting the i-th digit signal, i of the X register
The contents of digit X1 are decoded and a segment signal is output (n+s+n+6). If the content of Xi is “0”
9", the output of the segment signal is set as follows.

Turn off the i-th digit signal and increment digit counter i (n+7+n+s).

d) Repeat b) and c) until 10 digits are displayed (r++3).

e) If 10 digits are displayed, it is determined whether the key is manually operated. If there is key human power, the calculation will be executed, otherwise the display will be repeated (
n+4).

■ If there is key human power, perform calculations (n19 to n38).

a) First, if the MD flag is set, the calculation result is returned to the X register (n19+r+zo).

b) If it is the RoYoKoro] key, the MD flag is inverted (nz++n2z).

c) If it is the FEJEEJ key, TAB settings are performed. Pressure I field Every time the key is pressed, the TAB setting value changes as follows (n23~n27゜n37 + 1
38).

will be held. Each time the key is pressed, the rounding settings change as follows (n28 to n34) O e) For keys other than b), c), and d), MD
The flag is set, calculation is performed for each key, and the calculation result is stored in the X register (r+35°n36).
. If necessary during calculation, the TAB and rounding settings are referenced.

<Effects> As explained above, by implementing the present invention, electronic mode can be achieved using a display element with only Japanese character segments without providing a mode status display symbol or without using a display element capable of displaying characters. This makes it possible to realize a switch at a lower cost.

[Brief explanation of drawings]

;・)~ The operation explanatory diagram, FIG. 7, is a flowchart. Explanation of symbols CPU: Arithmetic processing unit, KEY: Key human resources department, DIS
P: Display section.

Claims (1)

[Claims] 1. An electronic desk calculator having a display section, characterized in that the electronic desk calculator is configured to display a set calculation mode state on a display element of only Japanese character segments.