AH = 46h: Set Display Timeout

This function enables the Auto-Timeout feature that will put the unit into deep sleep after a period of inactivity. The function also provides for setting the timeout interval. The test for Auto-Timeout occurs inside the Int 15h, Function 41xxh code.

• Input: AH = 46h
  BX = 1-65535: time out interval in 55 msec increments
  = 0 : Display timeout disabled

• Output: None
• Registers modified None

• The Auto-Timeout counter is TimOutCnt (40h:A1h). The counter reset value is TimOutVal (40h:A3h). TimOutCnt is decremented (but not past zero) by Timer0 Service.
• The power-up default for TimOutVal is 0CCCh (3 minutes).
• If the main batteries are low, the operating system reduces TimOutCnt to a maximum of 1 minute during the periodic Timer1 Service.