Oki OKIOFFICE 1200 Field Engineering Manual page 207

Setting of the Paper Size
Default setting: A4
When you install the second cassette, you must set the paper size for it.
1 Press Program key, B, 1, 0, 1, ENTER. The LCD shows:
1st Cassette :A4
←/→/Enter
2 Press ENTER to go to the setting for the second cassette. The LCD shows:
2nd Cassette :A4
←/→/Enter
← →
3 Press or of the cursor key until the recording paper size for the second cassette you want
appears. The A4, A5 or F4 sizes are available:
4 Press ENTER, ENTER.
Press STOP to return the machine to standby mode.
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