SEPTENTRIO AsteRx-m2a, Руководство по оборудованию

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AsteRx-m2a OEM
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2.5 I/O Connectors
The main connector is the 30-pin connector. That connector must always be connected.
The 60-pin connector provides additional signals (IO enable, serial CTS/RTS lines, GPIOs,
Ethernet, 10-MHz reference input, etc). That connector can be ignored and left
unconnected if these signals are not needed.
Warnings
•
All ground pins must be connected (not applicable to the 60-pin connector if that
connector is not used).
•
Do not drive a non-zero voltage into input pins (pins type “ I ” in the tables below)
when the receiver is not powered or is in standby (see section 2.9), and during the
first 300 ms after these states. The IO_EN pin of the 60-pin connector indicates
when the board is ready to accept input, and can be used to enable the drivers
driving the input pins. Designs not using the 60-pin connector must either keep
the input pins in hi-Z mode for at least 300 ms after applying power, or drive the
nRST pin low for at least 300 ms after applying power. When not using the IO_EN
pin, it is recommended not to put the board in standby mode.
•
When pull-up/down resistors are needed, use 10 k

.
•
Unused or reserved pins should be left unconnected unless explicitly mentioned
otherwise.
Conventions
•
Pin Type: I=Input, O=Output, P=Power, Ctrl=Control, Clk=Reference clock
• LVTTL=3V3 Low Voltage TTL: VI
L
≤ 0.8V, VI
H
≥ 2.0V, VO
L
≤ 0.4V, VO
H
≥ 2.4V.
•
PU: internally pulled up
• PD: internally pulled down
•
K: keeper input type
60 pin
30 pin