3Com PC Card User Manual page 49

S49 Bit-mapped. Storable.
Bit 4,3,2,1,0. Flow Control (&K CMD)
0 = No flow control
3 = Hardware flow control
4 = Modem to DTE, bidirectional flow control
8 = Modem to DTE, unidirectional flow control
12 = Modem to DTE, bidirectional, transparent flow control
16 = Modem to remote modem, bidirectional flow control
20 = DTE to modem to remote modem bidirectional flow control
Bit 5. Reserved.
Bit 6. Dumb mode.
0 = Smart mode
1 = Dumb mode
Bit 7. Compromise equalizer (%E CMD)
0 = Compromise equalizer enabled
1 = Compromise equalizer disabled
S Registers 45