LXD970A — Demo Board for 10/100 and 100BASE-FX Applications

12 Development Kit Manual

4.1.1 Function/Address Settings

The multi-function pins allow the user to enable or disable the applicable functions and determine

chip address according to the input level selected. Table 4 shows the status of the function

according to the (VMF) selection.

Table 4. Hardware Control Interface (JP1) Functions

Address Input Voltage Levels2
Pin Function VMF1VMF2VMF3VMF4
MF0
Address Bit 0 1 1 0 0
Auto-Negotiation
Sets the initial value of bit 0.12
Disabled
(0.12 = 0)
Enabled
(0.12 = 1)
Enabled
(0.12 = 1)
Disabled
(0.12 = 0)
MF1
Address Bit 1 1 1 0 0
Repeater / DTE Mode
Sets the initial value of bit 19.13
DTE
(19.13 = 0)
Repeater
(19.13 = 1)
Repeater
(19.13 = 1)
DTE
(19.13 = 0)
MF2
Address Bit 2 1 1 0 0
Nibble (4B) / Symbol (5B) Mode
Sets the initial value of bit 19.4
Nibble (4B)
(19.4 = 0)
Symbol (5B)
(19.4 = 1)
Symbol (5B)
(19.4 = 1)
Nibble (4B)
(19.4 = 0)
MF3
Address Bit 3 1 1 0 0
Scrambler Operation
Sets the initial value of bit 19.3
Enabled
(19.3 = 0)
Bypassed
(19.3 = 1)
Bypassed
(19.3 = 1)
Enabled
(19.3 = 0)
MF4
Address Bit 4 1 1 0 0
If Auto-Negotiate Enabled via MF0, MF4 works in combination with MAN2 (CFG1) to control
operating speed advertisement capabilities. See Table 5 for details.
If Auto-Negotiate Disabled
Then TX/F Mode
Sets the initial value of bit 19.2
100TX
(19.2 = 0)
100FX
(19.2 = 1)
100FX
(19.2 = 1)
100TX
(19.2 = 0)

Table 5. Operating Speed Advertisement Settings

MF4 Input
Voltage Levels1MAN2
(CFG1) Function
If Auto-Negotiate Enabled via MF0
VMF1, VMF4 Jumper Not Installed Advertise all capabilities, Ignore MAN1 (FDE)
VMF1, VMF4 Jumper Installed Advertise 10 Mbps only, Follow MAN1 (FDE)
VMF2, VMF3 Jumper Not Installed Advertise 100 Mbps only, Follow MAN1 (FDE)
VMF2, VMF3 Jumper Installed Advertise 10/100 Mbps, Follow MAN1 (FDE)
1. Input Voltage Levels (VMF1, VMF2, VMF3, VMF4) for MF pins.