1 files changed, 83 insertions, 0 deletions
diff --git a/doc/using/UART_srcs/vhpi/tty.c b/doc/using/UART_srcs/vhpi/tty.c
new file mode 100644
index 000000000..c04f8f359
--- /dev/null
+++ b/doc/using/UART_srcs/vhpi/tty.c
@@ -0,0 +1,83 @@
+/*
+  VPI code allowing you to connect terminal emulator or other program to pty "connected"
+  to the UART-like port in IP core simulated in GHDL.
+ 
+  This code is written by Wojciech M. Zabolotny (wz...@ise.pw.edu.pl) on 2nd June 2011
+  and is published as PUBLIC DOMAIN
+ 
+*/
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <stdarg.h>
+#include <unistd.h>
+#include <sys/types.h>
+#include <sys/ioctl.h>
+#include <linux/ioctl.h>
+#include <sys/stat.h>
+#include <sys/poll.h>
+#include <fcntl.h>
+#include <errno.h>
+
+char *ptsname(int fd);
+
+int ptyf = -1;
+
+
+
+int tty_open(int a)
+{
+  ptyf = open("/dev/ptmx",O_RDWR);
+  if(ptyf<0) {
+    perror("I can't open pseudoterminal\n");   
+    return -1;
+  }
+  if(unlockpt(ptyf)<0) {
+    perror("I can't unlock pseudoterminal\n");
+    return -1;
+  }
+  if(grantpt(ptyf)<0) {
+    perror("I can't grant pseudoterminal\n");
+    return -1;
+  }
+  printf("Pseudoterminal: %s\n",ptsname(ptyf));
+ // sleep(10);
+  return 0;
+}
+
+
+int read_enable(void)
+{
+  //In the masks below you may omit POLLHUP in this case
+  //disconnection of the terminal emulator from pty will not
+  //stop simulation, and you'll be able to reconnect
+  //the same or different program to pty and running simulation
+  struct pollfd pfd[1]={{ptyf,POLLIN | POLLERR | POLLHUP,0}};
+  int res;
+  res=poll(pfd,1,0);
+  if(res==0) return 0;
+  if(res<0) return 0; //error
+  //If you removed POLLHUP from the mask above, you should remove it below too
+  if(pfd[0].revents & (POLLERR|POLLHUP)) return 0; //disconnected or error?	
+  if(pfd[0].revents & POLLIN)       return 1;
+  return 0;
+}
+
+
+int read_data(void)
+{
+  unsigned char c;
+  read(ptyf,&c,1);
+  return c;
+}
+
+int write_data(int byte)
+{
+  unsigned char c = byte;
+  write(ptyf,&c,1);  
+
+  // Debug: printf("Writing %x to pty\n", c);
+  return 0;
+}
+