Dascom T2250 User Guide IGP for Dot Matrix Printers - Manual (Page 35)

Chapter 2: Emulations
35
VFU Data Format
The VFU Data Format includes two bytes of data for each line of the form, starting with line 1.
The two bytes of data indicate channel number(s). Traditionally, Channel 1 is reserved for Top-
Of-Form (TOF) and Channel 12 is reserved for Bottom-Of-Form (BOF). The Vertical Tab (VT)
Control Code moves the paper forward to the next marked tab position on Channel 2. The format
for the byte pair is:
Bit: 7 6 5 4 3 2 1 0
Value: x 1 C 6 C 5 C 4 C 3 C 2 C 1 Byte 1
x 1 C12 C11 C10 C 9 C 8 C 7 Byte 2
Where:
Bit 7 (x) = Not used.
Bit 6 = Always 1.
Bits 0–5 = VFU channels (C1–C12 = channels 1–12).
1 = channel present
0 = no channel
The byte-pairs for a sample load are shown below. The form length used for this example is 16
lines long; therefore, 16 byte-pairs are needed.
Byte Line Binary HEX Channel or Byte Line Binary HEX Channel or
# # Value Value Function # # Value Value Function
ESC[<1h Start Code
1 1 x1000001 4 1 1 1 7 9 x1000000 4 0
2 x1000000 4 0 1 8 x1000000 4 0
3 2 x1000000 4 0 1 9 10 x1000000 4 0
4 x1000000 4 0 2 0 x1000000 4 0
5 3 x1000000 4 0 2 1 11 x1100100 6 4 6 and 3
6 x1000000 4 0 2 2 x1000000 4 0
7 4 x1000000 4 0 2 3 12 x1000000 4 0
8 x1000000 4 0 2 4 x1000000 4 0
9 5 x1000000 4 0 2 5 13 x1000000 4 0
10 x1000000 4 0 2 6 x1000000 4 0
11 6 x1000000 4 0 2 7 14 x1000000 4 0
12 x1000000 4 0 2 8 x1000000 4 0
13 7 x1000010 4 2 2 2 9 15 x1000000 4 0
14 x1000000 4 0 3 0 x1100000 6 0 12
15 8 x1000000 4 0 3 1 16 x1001000 4 8 4
16 x1000000 4 0 3 2 x1000010 4 2 8
ESC[<1l Stop Code
Figure 10 – Sample VFU Download