SMSC TMC2005-JT - Manual (Page 8)

ARCNET 5 Port HUB Controller
Datasheet
Revision 1.1 (07-24-07) Page 8 SMSC TMC2005-JT
DATASHEET
FEATURE NAME INPUT/OUTPUT DESCRIPTION
mode.
The pulse is always active Low.
TX Port Polarity
Setup
LA, LB, LE INPUT Setup the polarity of TXENA
[0:1], TXENB [0:1], EXTTX.
0 : active L
1: active H
TX Port Mode Setup MA, MB, ME INPUT Setup the mode of TXENA [0:1],
TXENB [0:1], EXTTX.
0: Output TX pulse. (It is
equivalent to nTXEN “OR”
nP1BAK)
1: Output TX enable
Operating Mode Setup
FEATURE NAME
INPUT/
OUTPUT DESCRIPTION
Data rate
setup CKM [0:2] INPUT Terminal to setup the data rate of TMC2005.
CKM2 CKM1 CKM0 DIVISOR MULTIPLIER SPEED
0 0 0 16 x1 156.25 Kbps
0 0 1 8 x1 312.5 Kbps
0 1 0 4 x1 625 Kbps
0 1 1 2 x1 1.25 Mbps
1 0 0 1 x1 2.5 Mbps
1 0 1 1 x2 5 Mbps
1 1 0 Reserved Reserved Reserved
1 1 1 1 x4 10 Mbps
External clock is 20MHz.
Refer to “VARIOUS SETUP”
Noise cut
mode nMBA
nMBB
nMBE INPUT 0: Cut off noise from received data
1: Don’t cut off noise
Setup “0” normally.
Big jitter
mode nBJA
nBJB
nBJE INPUT Setup a jitter filter feature.
Select a pulse as reference phase used by DPLL.
0: 2
nd pulse (big jitter mode)
1: 1 st pulse (normal mode)
Open drain
mode nEXTOD INPUT Setup a the use of EXTTX port.
0: Set EXTTX as open drain output and use as Ext.
1: Set EXTTX as normal output and use as 5
th port.
PLL
FEATURE NAME
INPUT/
OUTPUT DESCRIPTION
LP OUTPUT Using PLL: Connect to an external condenser
“C1” for loop filter.
Using no PLL: must be open.
RO OUTPUT VCO output
Using PLL: Connect to an external resistor “R0” for
loop filter.
Using no PLL: must be open.
AGS INPUT Analog sense input.
Using PLL: Connect to loop filter.
Using no PLL: Connect to ground.