HelenOS sources

TCTL_EN          1706 uspace/drv/nic/e1k/e1k.c 	    E1000_REG_READ(e1000, E1000_TCTL) | (TCTL_EN));
TCTL_EN          1718 uspace/drv/nic/e1k/e1k.c 	    E1000_REG_READ(e1000, E1000_TCTL) & ~(TCTL_EN));
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