1 files changed, 56 insertions, 10 deletions

diff --git a/test.c b/test.c
index b24a2b7..24d6011 100644
--- a/test.c
+++ b/test.c
@@ -18,10 +18,17 @@
 #include <sys/mman.h>
 #include <unistd.h>
 #include <errno.h>
+#include <string.h>
 
 #define PAGE_SIZE (4*1024)
 #define BLOCK_SIZE (4*1024)
 
+#define SER_DAT_PIN   26
+#define SER_CLK_PIN   19
+#define GATE_PIN      13
+#define PAR_CLK_PIN    6
+#define SENSE_PIN      5
+
 int  mem_fd;
 void *gpio_map;
 
@@ -36,6 +43,7 @@ volatile unsigned *gpio;
 
 #define GPIO_SET *(gpio+7)  // sets   bits which are 1 ignores bits which are 0
 #define GPIO_CLR *(gpio+10) // clears bits which are 1 ignores bits which are 0
+#define GPIO_ALTER(a) *(gpio+(a==0?10:7))  // alters (a==0: clear, else: set)  bits which are 1 ignores bits which are 0
 
 #define GET_GPIO(g) (*(gpio+13)&(1<<g)) // 0 if LOW, (1<<g) if HIGH
 
@@ -44,6 +52,7 @@ volatile unsigned *gpio;
 
 void setup_io();
 void drop_privileges();
+void put_on_display(char *content);
 
 void printButton(int g)
 {
@@ -58,7 +67,7 @@ int main(int argc, char **argv)
   int rep;
 
   // Set up gpi pointer for direct register access
-  setup_io();
+//  setup_io();
 
   // Drop root privileges
   drop_privileges();
@@ -70,16 +79,18 @@ int main(int argc, char **argv)
   * so at least you still have your code changes written to the SD-card! *
  \************************************************************************/
 
-return 0;
-
-  INP_GPIO(21); // must use INP_GPIO before we can use OUT_GPIO
-  OUT_GPIO(21);
+  // must use INP_GPIO before we can use OUT_GPIO
+  INP_GPIO(SER_DAT_PIN);
+  OUT_GPIO(SER_DAT_PIN);
+  INP_GPIO(SER_CLK_PIN);
+  OUT_GPIO(SER_CLK_PIN);
+  INP_GPIO(GATE_PIN);
+  OUT_GPIO(GATE_PIN);
+  INP_GPIO(PAR_CLK_PIN);
+  OUT_GPIO(PAR_CLK_PIN);
+  INP_GPIO(SENSE_PIN);
 
-  for (rep=0; rep<2000000*60; rep++)
-  {
-     GPIO_SET = 1<<21;
-     GPIO_CLR = 1<<21;
-  }
+  put_on_display("0123456789abcdefghijklmnopqrstuvwxy");
 
   return 0;
 
@@ -136,3 +147,38 @@ void drop_privileges()
       exit(-1);
    }
 } // drop_root
+
+//
+// Shift the bits provided in content into the display
+//
+void put_on_display(char *content)
+{
+   char *raw_output;
+   int line;
+
+   raw_output = malloc(7*(5+1));
+   if (raw_output == NULL) {
+      perror("malloc failed");
+      exit(-1);
+   }
+   for (line=0; line<7; line++) {
+      raw_output[line*6] = 1<<line;
+      memmove(raw_output+1+6*line,content+5*line,5);
+   }
+   while (1);
+   for (line=0; line<7; line++) {
+      GPIO_CLR = 1<<GATE_PIN; // Licht an
+      for (int byte=0; byte<6; byte++) {
+         for (int bit=0; bit<8; bit++) {
+            GPIO_CLR = 1<<SER_CLK_PIN;
+            GPIO_ALTER((*(raw_output+6*line+byte)>>bit) & 0x01) = 1<<SER_DAT_PIN;
+            GPIO_SET = 1<<SER_CLK_PIN;
+         }
+      }
+      usleep(1000);
+      GPIO_SET = 1<<GATE_PIN; // Licht aus
+      GPIO_CLR = 1<<PAR_CLK_PIN;
+      GPIO_SET = 1<<PAR_CLK_PIN;
+   }
+   free(raw_output);
+} // put_on_screen