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Download (Exynos 4412) datasheet
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Exynos 4412_UM 17 Keypad Interface Figure 17-4 illustrates the keypad scanning procedure II. Interrupt generated and knows which H H Key Pressed (Short) H H H H H H H H H H H H H L H H H H H H H H H H H H GPIO KEY IF GPIO H KEY IF Read KEYIN register : All High if not matched SCAN_X[0] SCAN_X[0]“row” is pressed H SCAN_X[13] SCAN_X[13] SCAN_Y[0] SCAN_Y[0] H H H H H H H H L L L L L L L L SCAN_Y[7] SCAN_Y[7] Figure 17-4 Keypad Scanning Procedure II 17-5 Scan Procedure (S/W) : make one output LOW, the others HIGH and Read KEYIN
