IBM 4400 manual End Load Code-Hex 1F or 6F, Using the Evfu, Series Evfu

Chapter 9 P-Series EVFU

End Load Code-Hex 1F or 6F

The end load code terminates the memory load program. The end load code is hex 1F when the PI signal line is disabled (low) or hex 6F when the PI line is enabled (high). Channel codes in excess of 192 channels received prior to the end load code are discarded.

Using the EVFU

Once the EVFU program has been enabled and loaded, sending the appropriate channel code to the printer causes any data in the buffer to print and positions the paper to the next line on the form having the specified channel number assigned in EVFU memory.

For a data byte to be recognized as an EVFU instruction, the following criteria must be met:

•The PI signal line must be enabled and set high; and

•Data bit 5 must be 0 (not set).

OR:

•The PI signal line must be disabled or low; and

•Data bit 5 must be 1 (set).

Given these conditions, the lower four bits of a byte specifies the EVFU channel number. Table 77 lists the EVFU channels and their equivalent data bytes with the PI signal line enabled; Table 78 lists the EVFU channels and their equivalent data bytes with the PI line disabled.

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