Epson MFJ-1278B manual Saving Sstv Pictures to Disk, Terminating Sstv Printing

MFJ-1278B MULTI-MODE BASIC OPERATION

Coding: If, prior to unbiasing, the value of the data byte is an ASCII p, q, or r, then the received byte is a sync byte. Otherwise, the received byte contains actual display information as described above. The color level of each pixel contain in the data byte is given below:

000	001	110	111
white	lightest grey	darkest grey	black

NOTE: If the data byte is NOT a sync byte, you must remove the 30H bias BEFORE extracting the pixel information.

For example, if an ASCII '9' is received, then the following steps should be taken:

1.	Remove bias:	39H-30H = 9H
2.	Extract pixel information:	aaa = 001 bbb = 001
3.	Display two pixels of lighest grey level.

If an ASCII 'p', 'q', or 'r' is received, then process the byte as a sync tone.

Saving SSTV Pictures to Disk

When the PRINTGRA command of the MFJ-1278B is ON, SSTV pictures received will be sent to the graphics printer attached to the printer port. If PRINTGRA is OFF, the MFJ- 1278B will direct the picture graphics, in raw data format, to the user's terminal through the RS-232C port of the MFJ-1278B. If your terminal program allows you to save a file to disk, then you can save the picture on disk and re-transmit it later.

Terminating SSTV Printing

Printing of an SSTV picture can be terminated at any time during the printing. User will type "ESC" then CTRL-C. Printing will stop and the MFJ-1278B will return to command mode.

Transmitting SSTV Pictures

The MFJ-1278B is capable of transmitting color and up to 16 gray level B&W SSTV. To achieve this you must use a terminal program which support the multi-level SSTV data format required by the MFJ-1278B.

Each level of gray is represented by a tone produced by the MFJ-1278B modem. The 19 tones which can be produced by the MFJ-1278B FAX/SSTV modem (in Hz) are:

1100, 1200, 1300, 1500, 1550, 1600, 1650, 1700, 1750, 1800, 1850, 1900, 1950, 2000, 2050, 2100, 2150, 2200, and 2250.

The tone being transmitted determines the shade of gray in the picture. The sync tone of