Tag Archives: DIY electronics

Z80 8-bit Compact Flash Card Interface

Secondary storage is essential for most systems to hold programs for the long term. Attaching secondary storage to your system is a challenge, but a challenge worth investing time into. You can choose many different flavors of secondary storage to … Continue reading

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Z80 Monitor

Our system is just a heap of silicon unless it has some code to run. I don’t think the hardware is quite at the point of running an operating system like CP/M yet, but that doesn’t mean we can’t do … Continue reading

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UART Serial Terminal Output Test

  After sufficiently testing our EEPROM chips and with the knowledge that we are communicating with them properly we can start to build programs to test other devices added to our system. One of the more useful devices to add … Continue reading

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Interfacing and testing ROM chips – Part 2

It has been a long time since my last post. I hope to get back into regularly posting once or twice a week. This project has been on hold since starting another project that dominated my life. I recently built … Continue reading

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Interfacing and testing ROM chips – Part 1

EEPROM chips have come in. (CAT28C256) Now that we have a low frequency adjustable clock source and a single-stepping instruction interface to the Z80 processor we can test EEPROM chips after they have been programmed. Most every EEPROM chip consists … Continue reading

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Single Step Instruction Circuit

While¬†debugging you may find you would like to step through each instruction executed to assure that the function of your system is correct. Instead of cycling the clock over and over to get through each instruction with a single-step clock … Continue reading

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Z80 Test Circuit

Just think of how terrible it would be to wire up an entire system just to find out your microprocessor was a dud, and didn’t work properly. To avoid this we can build a test circuit to check if everything … Continue reading

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