SMSC PCM-2074, Руководство пользователя

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PCM-2074 EVB User Manual
Revision 1.0 (03-31-06)
USER MANUAL
SMSC PCM-2074
6
3.1 Configuring the Main Board
Table 3.1 and Table 3.2 below how to configure the Main Board using SW2.
3.2 Configuring the RS485 Board
Table 3.3 and Table 3.4 below show how to configure the RS485 Board.
Note: The Hub function is not used on the PCM-2074; SW1-2 should always be set in the default
position.
Table 3.1 SW2 (Main Board) Configuration Settings
POS. NAME DESCRIPTION
ON
(=0)
OFF
(=1) DEFAULT
8 MCKSEL1 Input clock frequency select, Bit 1 (MSB) See Table 3.2
below
10b
(20 Mhz)
7 MCKSEL0 Input clock frequency select, Bit 0 (LSB)
6 W16 Data Bus Width 8 16 8
5 WPRE1 Warning Timer 1, Bit 1 (MSB) Refer to TMC-
2074
Datasheet
11b
4 WPRE0 Warning Timer, Bit 0 (LSB)
3 NSTPRE2 NST Resolution, Bit 2 (MSB) Refer to TMC-
2074
Datasheet
000b
2 NSTPRE1 NST Resolution, Bit 1
1 NSTPRE0 NST Resolution, Bit 0 (LSB)
Table 3.2 Input Clock Configuration
MCKSEL1 MCKSEL0 CLOCK FREQ. MAX BAUD RATE
1 1 40 Mhz 5 Mbps
1 0 20 Mhz 2.5 Mbps
0 1 10 Mhz 1.25 Mbps
0 0 Reserved
Table 3.3 SW1 (RS485 Board) Configuration Settings
POS. NAME DESCRIPTION ON OFF DEFAULT
SW1-2 nHubON Enables Hub Mode Hub* No Hub No Hub
SW1-1 nCMIBYP Selects CMI or RZ mode RZ CMI CMI
Table 3.4 JP1, JP2 (RS485 Board) Configuration Settings
POS. NAME DESCRIPTION SHORT OPEN DEFAULT
JP1, JP2 (Offset
Resistor)
Connects or disconnects Offset
Resistors; both jumpers must be
set the same way
Connected Dis-
connected
Connected