Choosing between a 7 or 8 bit VT emulation type-WC
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We are transferring our site (Data Bases & emulations) from 7 bit to 8 bit. The emulation found to be suitable for that purpose is VT220-7. When we tried to use VT220-8 I noticed that the use of "upper-arrow" (which is used in Unix to show the previous command) did not function in the right way, while with VT220-7 works as expected. What is the meaning of the 7 or 8 in the VT220? Is there any problem with working with VT220-7 for full 8 bit environment? Can I configure the VT220-8 to work the same way as VT220-7 while using the "upper-arrow"?

In regards to your questions about moving from 7 to 8 bits:
Changing to VT 220-8 has to do with the way escape sequences are sent:

  1. Using VT 220-8 a "CSI" will be sent as "CSI" char (hex 9B).
  2. Using VT 220-7 it will be sent as a 2 bytes sequence esc [ (hex 1B 5B).

The "upper arrow" is CSI A (i.e. esc [ A ) in -7 mode.; you need to do the following:

  1. Open WebConnect Administration Tool.
  2. Double click on the relevant connection.
  3. Click the Settings button.
  4. In the Emulation tab choose a VT###-7 terminal type.
  5. In the General tab check the "Use 8 Bit Data Characters" check box.