At89c2051 Projects ((link)) -

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Advanced Components: 4-digit common cathode 7-segment display, 4x PNP transistors (or ULN2003), 8x resistors at89c2051 projects

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void main() unsigned char led = 0x01; unsigned char dir = 0; // 0 left, 1 right 4x PNP transistors (or ULN2003)

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