--- /dev/null
+/*
+ * testprogram for _sys() function on Atari
+ *
+ * 17-Sep-2013, chris@groessler.org
+ *
+ * uses PUTCHR IOCB function to display a string
+ */
+
+#include <atari.h>
+#include <6502.h>
+#include <conio.h>
+
+static struct regs regs;
+static struct __iocb *iocb = &IOCB; /* use IOCB #0 */
+
+static char message[] = "I'm the sys test text\n";
+
+int main(void)
+{
+ /* setup IOCB for CIO call */
+ iocb->buffer = message;
+ iocb->buflen = sizeof(message) - 1;
+ iocb->command = IOCB_PUTCHR;
+
+ /* setup input registers */
+ regs.x = 0; /* IOCB #0 */
+ regs.pc = 0xe456; /* CIOV */
+
+ /* call CIO */
+ _sys(®s);
+
+ if (regs.y != 1)
+ cprintf("CIO error 0x%02\r\n", regs.y);
+
+ cgetc();
+ return 0;
+}