Quote:
Originally Posted by guybrush
My LED turn on; it is not turning off to show activity; but instead is showing the state of the SD2IDE adapter
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Not really. The problem is a bit different and is caused by the fact that SD2IDE uses 3.3 V logic levels. Pin 39 of the IDE bus signals drive activity and controls Amiga HDD LED. It is active low signal, so the converter sets pin to 0V when the card is active and to 3.3 V when it is inactive. Note that regular HDD will set the pin to somewhere between 4.5 to 5.0 V when inactive.
Amiga 1200 uses a simple circuit with a PNP bipolar transistor to drive the HDD LED. At 0.0 V on pin 39 transistor is turned on, LED lits. At voltages above about 4.3 V the transistor turns off. Now you see the problem. While for the SD2IDE 3.3 V means "inactive", transistor will stay turned on. So LED will lit permanently, ignoring any activity changes.
Fixes for the problem have been listed by LIV2, above.