SBC-984
SBC-984 User Manual - Rev. First Edition: 1.0 - Last Edition: 4.0 - Author: S.B. - Reviewed by N.P. Copyright © 2016 SECO S.r.l.
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SMB_DAT: SM Bus control data line for System Management. Bidirectional signal, electrical level +3.3V_S with a 4k7
Ω
pull-up resistor.
/ USB_H1-: Secondary USB Port #1 differential pair; it is managed by SMSC USB2412 secondary USB Hub controller, Downstream Port #1.
Slot_ENABLE#: this signal allows setting in high-impedance state the differential pairs available on pins 23/25 and 31/33. When signal is LOW, then normal
operation of the slot is enabled, and selection between miniPCI Express and mSATA working mode is made using signal mSATA_SEL. When Slot_ENABLE# signal
is HIGH, then these interfaces on the slot are disabled and power consumption is reduced. Please consider that even if these interfaces are disabled, the slot can
still be used with USB interface. Input signal, electrical level +3.3V_S with a 33k
Ω
pull-up resistor. Enabling of these interfaces is automatic upon insertion of
miniPCI-e or mSATA modules, since both of them, according to respective specifications, must tie this pin to GND.
mSATA_SEL: this signal is needed for selection between SATA and PCI-express interface: when mSATA_SEL is LOW, then PCI-express is available. When
mSATA_SEL is HIGH, then SATA interface is available. Input signal, electrical level +3.3V_S with a 33k
Ω
pull-up resistor. Selection is automatic since, according to
their respective specifications, miniPCI-express modules have to tie to GND this signal, while mSATA modules must left it unconnected (this means that the signal
goes automatically high, due to on-board pull-up).
3.3.7
Serial port RS-232
NXP i.MX6 processor offers some native serial ports. On SBC-984 board, one of them (UART5) is used
for external communications.
Electrical interface of such a port is TTL, for this reason on the board has been integrated an RS-232
transceiver, which gives the possibility (through a simple adapter cable) to connect the serial port to
standard COM ports, like those available on common Desktop PCs and other devices.
This serial port is accessible through a 5-pin connector, type MOLEX p/n 53398-0571 or equivalent.
Mating connector: MOLEX 51021-0500 receptacle with MOLEX 50079-8000 female crimp terminals.
If neededy, SECO can provide for a DB-9 male adapter cable for direct connection of RS-232 peripherals. Please
check par. 4.2.5.
Signals
’
description:
TX: Serial port Interface, data transmit line, ± 15kV ESD Protected, RS-232 level transmitter output.
RX: Serial port interface, data receive line, ± 15kV ESD Protected, RS-232 compatible receiver input.
RS-232 Interface - J5
Pin Signal
1
TX
2
RX
3
---
4
CTS#
5
GND
