Logic Circuits for Computer Education in Junior High School
Grant-in-Aid for Scientific Research (C)
|Allocation Type||Single-year Grants|
|Research Institution||Yamanashi University|
FUJITA Takao Yamanashi University, Faculty of Education and Human Science, Associate Professor, 教育人間科学部, 助教授 (10091737)
|Project Period (FY)
1997 – 1998
Completed(Fiscal Year 1998)
|Budget Amount *help
¥1,700,000 (Direct Cost : ¥1,700,000)
Fiscal Year 1998 : ¥500,000 (Direct Cost : ¥500,000)
Fiscal Year 1997 : ¥1,200,000 (Direct Cost : ¥1,200,000)
|Keywords||computer / information / logic / circuit / transistor / IC / HL / HFL / computer / intermetion / 情報基礎 / 情報教育 / コンピュータ / 論理回路|
a) Logic Elements by Transistors
In order to show that logic ICs can be made from transistors and not to treat then as "black box", NAND, NOR.and NOT elements are composed of 2 or 1 transistors by the method of DCTL (Direct Coupling Transistor Logic). They are not TTL type, but, the principle is easy to understand.
b) HFL Checker
H and L mean High(1) and Low(0) logic levels, respectively. F means electrical float state or no input state to IC input terminals. This developed HFL checker can differentiate this 3 states in order to detect circuit conditions. This checker is composed of 1 transistor and 1 NOT element in principle.
c) TTL Pulse Oscillator with Period 1 sec.
In various experiments on logic circuits, TTL oscillator with low frequency is. useful for observing releated results with eyes. The 50 Hz signal from a power line is reduced to TTL 1Hz signal by using transformer, diode, NOT and counter(50).
d) Checker for "Which has switch A and B been pressed quickly? "
In a simple RS-FF with 2 NORs, R=S=1 are forbidden because of a racing phenomenon etc.. But, this phenomenon means that a quicker response to R/S terminal can be checked. This idea is expaded in this checker. Since this checker has the fundamental 5 mechanisms of computer(input, output, computation, memory, control), we can say that this is a "computer" in spite of a simple structure.
e) Measuring by/Control to Digital Oscilloscope
By using RS232C interfaces between a digital oscilloscope and a personal computer, the application tool for measuring by and contolling to digital oscilloscope is developed in order to observe signals from electric and logic circuits. Signal processing, data saving/loading and printing out etc. are enable.
Research Output (12results)