Hola Denis!
 > When a character is received, it generates an interrupt which
 > goes back to the terminal. The terminal would then hopefully save the byte
 > to disk and then exit. The computer would be switching back and forth
 > between the terminal and the TSR.
 Okay, here is what i understand of this.
  |Terminal|                       Goes back to terminal  <--=
      |                            Save the byte, but how     |
 |Key pressed| -> |TSR program|    it returns control to      |
                      |            TSR program. And how       |
                      |            it doesn't overwrite the   |
                      |            current TSR window?        |
                      |                                       |
                  |Irq interrupt| (bytes received) -----------
 > everything down. For example, if I load the VSAFE TSR and pop
 > it up, my
 > blinky program stops.
Hum,
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