VT510 Video Terminal Programmer Information

DECSRFR—Select Refresh Rate

Selects a refresh rate.

Format

CSI
9/11
Ps
3/n
"
2/2
t
7/4

Parameters

Ps
indicates the refresh rate selection. On the VT510, only 60 Hz and 72 Hz are supported.

Ps Refresh Rate
1 50 Hz
2 60 Hz
3, 0 or none Greater or equal to 70 Hz

Description

The terminal can be set to refresh its display at the power line frequency in electrically noisy environments. Normally this is unnecessary. The 72 Hz refresh rate is preferred to minimize flicker.

Because of a hardware limitation, overscan and 72 Hz refresh rate cannot co-exist when the lines per screen is set to 42 or 53. See DECSNLS for details. If a combination of lines per screen, refresh rate, and overscan become invalid, then the terminal returns to a valid combination in this order of priority:

  1. Lines Per Screen
  2. Refresh Rate
  3. Overscan