Diff: u8g_com_atmega_st7920_spi.c

Revision:

0:972874f31c98

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/u8g_com_atmega_st7920_spi.c	Wed Mar 07 12:49:14 2018 +0000
@@ -0,0 +1,171 @@
+/*
+  
+  u8g_com_atmega_st7920_spi.c
+
+  Universal 8bit Graphics Library
+  
+  Copyright (c) 2011, olikraus@gmail.com
+  All rights reserved.
+
+  Redistribution and use in source and binary forms, with or without modification, 
+  are permitted provided that the following conditions are met:
+
+  * Redistributions of source code must retain the above copyright notice, this list 
+    of conditions and the following disclaimer.
+    
+  * Redistributions in binary form must reproduce the above copyright notice, this 
+    list of conditions and the following disclaimer in the documentation and/or other 
+    materials provided with the distribution.
+
+  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND 
+  CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, 
+  INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 
+  MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE 
+  DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR 
+  CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 
+  SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 
+  NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 
+  LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER 
+  CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, 
+  STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 
+  ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF 
+  ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.  
+
+  A special SPI interface for ST7920 controller
+
+*/
+
+#include "u8g.h"
+
+#if defined(__AVR__)
+
+static void u8g_atmega_st7920_sw_spi_shift_out(u8g_t *u8g, uint8_t val) U8G_NOINLINE;
+static void u8g_atmega_st7920_sw_spi_shift_out(u8g_t *u8g, uint8_t val)
+{
+  uint8_t i = 8;
+  do
+  {
+    u8g_SetPILevel(u8g, U8G_PI_MOSI, val & 128 );
+    val <<= 1;
+    u8g_SetPILevel(u8g, U8G_PI_SCK, 1 );
+    u8g_MicroDelay();		/* 15 Aug 2012: added for high speed uC */
+    u8g_SetPILevel(u8g, U8G_PI_SCK, 0 );
+    u8g_MicroDelay();		/* 15 Aug 2012: added for high speed uC */
+    i--;
+  } while( i != 0 );
+}
+
+static void u8g_com_atmega_st7920_write_byte(u8g_t *u8g, uint8_t rs, uint8_t val) U8G_NOINLINE;
+static void u8g_com_atmega_st7920_write_byte(u8g_t *u8g, uint8_t rs, uint8_t val)
+{
+  uint8_t i;
+  
+  if ( rs == 0 )
+  {
+    /* command */
+    u8g_atmega_st7920_sw_spi_shift_out(u8g, 0x0f8);
+  }
+  else if ( rs == 1 )
+  {
+    /* data */
+    u8g_atmega_st7920_sw_spi_shift_out(u8g, 0x0fa);
+  }
+  
+  u8g_atmega_st7920_sw_spi_shift_out(u8g, val & 0x0f0);
+  u8g_atmega_st7920_sw_spi_shift_out(u8g, val << 4);
+
+  for( i = 0; i < 4; i++ )
+    u8g_10MicroDelay();
+}
+
+
+uint8_t u8g_com_atmega_st7920_sw_spi_fn(u8g_t *u8g, uint8_t msg, uint8_t arg_val, void *arg_ptr)
+{
+  switch(msg)
+  {
+    case U8G_COM_MSG_INIT:
+      u8g_SetPIOutput(u8g, U8G_PI_SCK);
+      u8g_SetPIOutput(u8g, U8G_PI_MOSI);
+      /* u8g_SetPIOutput(u8g, U8G_PI_A0); */
+      u8g_SetPIOutput(u8g, U8G_PI_CS);
+      u8g_SetPIOutput(u8g, U8G_PI_RESET);
+      
+      u8g_SetPILevel(u8g, U8G_PI_SCK, 0 );
+      u8g_SetPILevel(u8g, U8G_PI_MOSI, 0 );
+      u8g_SetPILevel(u8g, U8G_PI_CS, 0 );
+      /* u8g_SetPILevel(u8g, U8G_PI_A0, 0); */
+    
+      u8g->pin_list[U8G_PI_A0_STATE] = 0;       /* inital RS state: command mode */
+      break;
+    
+    case U8G_COM_MSG_STOP:
+      break;
+
+    case U8G_COM_MSG_RESET:
+      u8g_SetPILevel(u8g, U8G_PI_RESET, arg_val);
+      break;
+    
+    case U8G_COM_MSG_ADDRESS:                     /* define cmd (arg_val = 0) or data mode (arg_val = 1) */
+      u8g->pin_list[U8G_PI_A0_STATE] = arg_val;
+      break;
+
+    case U8G_COM_MSG_CHIP_SELECT:      
+      if ( arg_val == 0 )
+      {
+        /* disable, note: the st7920 has an active high chip select */
+        u8g_SetPILevel(u8g, U8G_PI_CS, 0);
+      }
+      else
+      {
+        /* u8g_SetPILevel(u8g, U8G_PI_SCK, 0 ); */
+        /* enable */
+        u8g_SetPILevel(u8g, U8G_PI_CS, 1); /* CS = 1 (high active) */
+      }
+      break;
+      
+
+    case U8G_COM_MSG_WRITE_BYTE:
+      u8g_com_atmega_st7920_write_byte(u8g, u8g->pin_list[U8G_PI_A0_STATE], arg_val);
+      u8g->pin_list[U8G_PI_A0_STATE] = 2; 
+      break;
+    
+    case U8G_COM_MSG_WRITE_SEQ:
+      {
+        register uint8_t *ptr = arg_ptr;
+        while( arg_val > 0 )
+        {
+          u8g_com_atmega_st7920_write_byte(u8g, u8g->pin_list[U8G_PI_A0_STATE], *ptr++);
+	  u8g->pin_list[U8G_PI_A0_STATE] = 2; 
+          arg_val--;
+        }
+      }
+      break;
+
+      case U8G_COM_MSG_WRITE_SEQ_P:
+      {
+        register uint8_t *ptr = arg_ptr;
+        while( arg_val > 0 )
+        {
+          u8g_com_atmega_st7920_write_byte(u8g, u8g->pin_list[U8G_PI_A0_STATE], u8g_pgm_read(ptr));
+	  u8g->pin_list[U8G_PI_A0_STATE] = 2; 
+          ptr++;
+          arg_val--;
+        }
+      }
+      break;
+  }
+  return 1;
+}
+
+#else
+
+
+uint8_t u8g_com_atmega_st7920_sw_spi_fn(u8g_t *u8g, uint8_t msg, uint8_t arg_val, void *arg_ptr)
+{
+  return 1;
+}
+
+
+#endif
+
+