Pancyprian TS Dig. Electronics II case studies
Pancyprian TS Dig. Electronics II · Put your knowledge to work in context.
The Pancyprian Technical School Digital Electronics II examination is a subject exam within Cyprus's technical secondary education system, typically taken by students completing the Digital Electronics II course in technical school programmes. It is intended for candidates who already understand basic logic gates and now need to design, analyse and troubleshoot complete digital systems. The Pancyprian TS Dig. Electronics II case studies are 5 cases and about 4,242 words.
1Calibration offset register and a don't-care BCD decoder
A bench calibration unit for a thermocouple press-fit station stores its sensor offset in an 8-bit two's complement register: 0x00–0x7F are positive counts and 0xFF–0x80 negative ones. The maintenance screen shows the register in hexadecimal only.
857 words, about 4 min2Static hazard on a relay-selector enable line
The relay selector of an environmental chamber routes one of eight sensor channels to a chart recorder. A 3-bit channel address from the front-panel selector feeds a decoder built from 74HC00 NAND gates (tpd 9 ns typical at 4.5 V, three levels deep).
909 words, about 5 min3Mod-12 carton counter with an asynchronous clear
A box-filling line packs 12 items per carton. The counter is two cascaded 74HC161 synchronous counters clocked directly by a photoelectric sensor at up to 300 items per minute.
865 words, about 4 min4SRAM address aliasing on an 8051 memory board
An 8051 board carries a 6264 8K×8 SRAM (A0–A12, /CE1, CE2, /OE, /WE) and a 27C256 32K EPROM (A0–A14). The EPROM's /CE is driven from A15 through a gate, so it answers only in 0x8000–0xFFFF.
792 words, about 4 min5Ten-bit weigh-scale ADC versus a 12-bit upgrade
A weighing platform uses a 10-bit SAR ADC with a 4.096 V reference, sampling the load-cell amplifier output at 1 kSa/s. The analog front end presents 1.2 mV rms of broadband noise, and the amplifier output swings between 0.2 V and 3.9 V over the 3 kg range.
819 words, about 4 min