_ DEC-O-LOG for VTX20 _ DOL, VTX20-I001, TERMINAL DEC 87 PROBLEM: Firmware version 1.2 does not properly allow the VTX20 to display Videotex frames under all circumstances in that the Videotex emulation is not to specifications. Output voltage on DBT03 modem port can drop below specified minimum resulting in Videotex modes. Entering VTX setup from VT220 mode temporarily interrupts port 1 data flow. Control of backward channel when using a V23 modem is not supported. If no modem control is selected, the DTR and RTS lines are held low instead of high. Videotex emulation problems: 1. VTX20 does not fully meet the PRESTEL specification regarding removal of attributes when writing to a cell with attributes. 2. VTX20 does not treat mosaic character set as an attribute. 3. At slow reception speeds, VTX20 does not correctly display separate mosaics. 4. Writing the bottom row of double height characters does not delete exiting text on that row. 5. Attempts to optimize handling of some attributes means that they extend across areas they should not. 6. If no modem control is selected in PRESTEL mode, the F10 key should send the "exit" command, but does not. 7. After a recall to factory set parameters, VTX20 may attempt to use a BTX parser, even though PRESTEL is selected. 8. Using modem control in BTX mode, the terminal may hang after exiting a remote session. Symptoms: 1. Attributes are not removed when writing new text to a cell. 2. Mosaic characters appear as ASCII text. 3. Areas that should have cross hatch shading appear solid. 4. Some spurious data appears on the same row as the bottom row of double height characters. 5. Attributes can extend beyond their originally defined areas. 6. Pressing F10 has no effect. 7. Display appears garbled. 8. VTX20 hangs after disconnecting from a remote BTX session. FIELD EFFECTIVITY: This FCO applies to VTX20s shipped with version 1.2 firmware, and Field Service spares with 1.2 firmware. The serial number range is VL0000111 to VL0000554. It is restricted to the European area. This FCO implements ECO: VTX01-ML002. QUICK CHECK: This FCO is not required if the firmware version displayed on any Videotex Set-Up screen is V2.2 or greater, or if the firmware ROMs are marked V2.2 or greater. FCO KIT ORDERING: EQ-01498-01 FCO, PARTS FA-04793-01 FCO only