Initial revision

diff --git a/v7/src/microcode/gpio.c b/v7/src/microcode/gpio.c
new file mode 100644 (file)
index 0000000..bec52b3
--- /dev/null
+++ b/v7/src/microcode/gpio.c
@@ -0,0 +1,118 @@
+/* -*-C-*-
+
+Copyright (c) 1990 Massachusetts Institute of Technology
+
+This material was developed by the Scheme project at the Massachusetts
+Institute of Technology, Department of Electrical Engineering and
+Computer Science.  Permission to copy this software, to redistribute
+it, and to use it for any purpose is granted, subject to the following
+restrictions and understandings.
+
+1. Any copy made of this software must include this copyright notice
+in full.
+
+2. Users of this software agree to make their best efforts (a) to
+return to the MIT Scheme project any improvements or extensions that
+they make, so that these may be included in future releases; and (b)
+to inform MIT of noteworthy uses of this software.
+
+3. All materials developed as a consequence of the use of this
+software shall duly acknowledge such use, in accordance with the usual
+standards of acknowledging credit in academic research.
+
+4. MIT has made no warrantee or representation that the operation of
+this software will be error-free, and MIT is under no obligation to
+provide any services, by way of maintenance, update, or otherwise.
+
+5. In conjunction with products arising from the use of this material,
+there shall be no use of the name of the Massachusetts Institute of
+Technology nor of any adaptation thereof in any advertising,
+promotional, or sales literature without prior written consent from
+MIT in each case. */
+
+/* $Header: /Users/cph/tmp/foo/mit-scheme/mit-scheme/v7/src/microcode/Attic/gpio.c,v 1.1 1990/06/12 16:35:28 jinx Exp $ */
+\f
+/* Scheme primitives for GPIO */
+
+#include "scheme.h"
+#include "prims.h"
+
+#include <stdio.h>
+#include <fcntl.h> 
+#include <dvio.h>
+
+
+DEFINE_PRIMITIVE ("OPEN-GPIO", Prim_open_gpio, 1, 1, 0)
+{
+  int gpio_channel;
+
+  PRIMITIVE_HEADER (1);
+
+  gpio_channel = open (STRING_ARG (1), O_RDWR);
+  if (gpio_channel == -1) error_external_return();    
+
+  io_reset (gpio_channel);
+  io_width_ctl (gpio_channel, 16);
+  
+  PRIMITIVE_RETURN( long_to_integer (gpio_channel));
+}
+
+
+DEFINE_PRIMITIVE ("READ-GPIO", Prim_read_gpio, 1, 1, 0)
+{
+  int gpio_channel;
+  unsigned long result;
+  unsigned char buffer[4];
+  int xfer;
+
+  PRIMITIVE_HEADER (1);
+
+  gpio_channel = arg_integer(1);
+
+  buffer[0] = ((unsigned char) 0);
+  buffer[1] = ((unsigned char) 0);
+
+  xfer = read (gpio_channel, &buffer[0], 2);
+
+  if (xfer != 2) error_external_return();
+
+  result = ((unsigned long) buffer[1]);
+  result = (result + (((unsigned long) buffer[0]) << 8));
+
+  PRIMITIVE_RETURN( long_to_integer (result));
+}
+
+
+DEFINE_PRIMITIVE ("WRITE-GPIO", Prim_write_gpio, 2, 2, 0)
+{
+  int gpio_channel;
+  unsigned long output;
+  unsigned char buffer[4];
+  int xfer;
+
+  PRIMITIVE_HEADER (2);
+
+  gpio_channel = (arg_integer (1));
+  output = (arg_integer (2));
+
+  buffer[1] = (output & 0xff);
+  buffer[0] = ((output >> 8) & 0xff);
+
+  xfer = write (gpio_channel, &buffer[0], 2);
+
+ /* xfer is 2 if successfull */
+ 
+  PRIMITIVE_RETURN( long_to_integer( xfer ));
+}
+
+DEFINE_PRIMITIVE ("CLOSE-GPIO", Prim_close_gpio, 1, 1, 0)
+{
+  int gpio_channel;
+
+  PRIMITIVE_HEADER (1);
+
+  gpio_channel = (arg_integer (1));
+  close ( gpio_channel );
+  
+  PRIMITIVE_RETURN( long_to_integer( gpio_channel ));
+}