There are many pcs being used at CTIO to log onto the mainframe computers. this is done by running an emulator program on the pc which makes it simulate, more or less, a vt100+retrographics terminal. If the pc is off, turning it on will boot the disk. If the pc is on but nothing is setup, ie; the prompt looks like " A> ", then you can run the emulator by typing vt. Most of the pcs are equiped with hard disks. For those that are not; check to see that the correct floppy is installed. If this doesn't work, boot the disk again by typing Alt/Shift/Delete. Press all three keys at the same time. Then type vt again. Once the pc runs the emulator, type return several times. On the mountain each pc is connected directly to a specific SUN computer; you should get the normal login prompt for that computer. In La Serena the pcs are connected to a micom terminal switcher, which allows them to be used to log on to any of the La Serena computers. You will then be prompted for the number of the computer you wish to log onto, so type the number and hit return. You may now log onto the computer at the prompt.

If you are logged in and using IRAF from a pc, it is a good idea to set the terminal to the proper identification. This helps when you are using the help facility for example by setting the screen size to the proper format. Do this by typing;

      cl> stty pc640

This will properly set the terminal type.

There is a difference between text and graphics screens and there are two commands which link the two. In the vt100 screen you press Alt g to get into graphics mode. To get back to the text screen, type F3 or Alt v. In graphics mode, for terminals which have only one arrow keypad, the cursor movement is in small steps, but using shift and the arrow gives larger steps. For terminals which have two arrow keypads, use the cursor pad key. The numlock key will light up as well. This uses the far right keypad for small increments and the left one for large increments in the cursor movement.

When you are finished first log off the mainframe computer in the normal way. In La Serena you must then type Alt/Shift b (type all three at once) to break the connection between the micom and the host computer. Finally, you can type Alt x to exit from the emulator program. The Ctrl/Shift key toggles back and forth between using the terminal emulator to talk to the mainframe and talking directly to the pc. You can safely switch back and forth without logging out, and can even leave a program running on the sun while you play chess on the pc.