IBM 4400-006 - 4400 Model 006 B/W Direct Thermal User Manual page 29

6. Ethernet in Auto mode in 10mbps HD environment
(determined using 10hd hub)
Use auto-negotiation to the highest common local and remote
capability, i.e. 100FD in this case.
PORs to 10HD. Resets to 10HD. Reconnection at switch
maintains 10HD.
NOTE: With parallel detection, only speed can be determined. The
duplex mode sets to half duplex.
Speed Setting for 10/100Base-T
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