# HG changeset patch
# User Paul Boddie <paul@boddie.org.uk>
# Date 1475526347 -7200
# Node ID 1f51b3efd042851c72144c57e4492139accbb133
# Parent  aee4b1c755b549b61afb604402c3ee34d7167c5a
Adjusted GPIO usage and added a form of visual feedback. Unfortunately, it
appears that GPIO locations are not accessible in user mode, even through the
memory management unit.

diff -r aee4b1c755b5 -r 1f51b3efd042 stage2/tasks/keyscan.c
--- a/stage2/tasks/keyscan.c	Mon Oct 03 22:24:54 2016 +0200
+++ b/stage2/tasks/keyscan.c	Mon Oct 03 22:25:47 2016 +0200
@@ -20,10 +20,45 @@
 #include "board.h"
 #include "tasks.h"
 #include "task_gpio.h"
+#include "jzlcd.h"
+#include "lcd.h"
+
+extern vidinfo_t panel_info;
+
+void plot_value(unsigned short xmin, unsigned short xmax, unsigned short ymin, unsigned short ymax, u8 value)
+{
+	unsigned short x, y;
+	u32 pixel;
+
+	for (y = ymin; (y < panel_info.vl_row) && (y < ymax); y++)
+	{
+		pixel = (value >> (((y - ymin) * 8) / (ymax - ymin))) % 2 ? 0xffffffff : 0;
+
+		for (x = xmin; (x < panel_info.vl_col) && (x < xmax); x++)
+		{
+			set_pixel(x, y, pixel);
+		}
+	}
+}
+
+void init_keyscan()
+{
+	int column;
+
+	for (column = 0; column < GPIO_KEYOUT_COUNT; column++)
+	{
+		task_gpio_set_pin(GPIO_KEYOUT_BASE + column);
+	}
+}
+
+/* Tasks. */
 
 void keyscan(unsigned short task)
 {
-	int column, row, value;
+	int column, row;
+	u8 value;
+
+	init_keyscan();
 
 	while (1)
 	{
@@ -31,17 +66,20 @@
 
 		for (column = 0; column < GPIO_KEYOUT_COUNT; column++)
 		{
-			task_gpio_set_pin(GPIO_KEYOUT_BASE + column);
+			task_gpio_clear_pin(GPIO_KEYOUT_BASE + column);
+
 			value = 0;
 
 			for (row = 0; row < GPIO_KEYIN_COUNT; row++)
 			{
-				value = (value << 1) | task_gpio_get_pin(GPIO_KEYIN_BASE + row);
+				value = (value << 1) | !task_gpio_get_pin(GPIO_KEYIN_BASE + row);
 			}
 
 			/* Perform an operation indicating the status. */
 
-			task_gpio_clear_pin(GPIO_KEYOUT_BASE + column);
+			plot_value(column * 10, column * 10 + 10, 0, 10 * GPIO_KEYIN_COUNT, value);
+
+			task_gpio_set_pin(GPIO_KEYOUT_BASE + column);
 		}
 	}
 }