SRS Labs SIM928, Руководство по эксплуатации и обслуживанию

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1.3 SIM Interface 1 – 7
Direction
Pin Signal Src
⇒
Dest Description
1 SIGNAL GND MF
⇒
SIM Ground reference for signal
2
−
STATUS SIM
⇒
MF Status
/
service request (GND
=
asserted,
+
5 V
=
idle)
3 RTS MF ⇒ SIM HW handshake (
+
5 V
=
talk; GND
=
stop)
4 CTS SIM ⇒ MF HW handshake (
+
5 V
=
talk; GND
=
stop)
5 − REF 10MHZ MF ⇒ SIM 10 MHz reference (optional connection)
6 − 5 V MF ⇒ SIM Power supply (no connection in SIM928)
7 − 15 V MF ⇒ SIM Power supply (battery charger)
8 PS RTN MF ⇒ SIM Power supply return
9 CHASSIS GND Chassis ground
10 TXD MF ⇒ SIM Async data (start bit
=
“0”
= +
5 V; “1”
=
GND)
11 RXD SIM ⇒ MF Async data (start bit
=
“0”
= +
5 V; “1”
=
GND)
12
+
REF 10MHz MF ⇒ SIM 10 MHz reference (optional connection)
13
+
5 V MF ⇒ SIM Power supply (digital circuitry)
14
+
15 V MF ⇒ SIM Power supply (no connection in SIM928)
15
+
24 V MF ⇒ SIM Power supply (battery charger)
Table 1.1: SIM Interface Connector Pin Assignments, DB-15
1.3.2 Direct interfacing
The SIM928 is intended for operation in the SIM900 Mainframe, but
users may wish to directly interface the module to their own systems
without the use of additional hardware.
The mating connector needed is a standard DB–15 receptacle, such as
Amp part # 747909-2 (or equivalent). Clean, well-regulated supply
voltages of
− 15,
+
5,
+
24 VDC must be provided, following the pin-out
specified in Table 1.1. Ground must be provided on pins 1 and 8,
with chassis ground on pin 9. The
− STATUS signal may be monitored
on pin 2 for a low-going TTL-compatible output indicating a status
message.
1.3.2.1 Direct interface cabling
If the user intends to directly wire the SIM928 independent of the
SIM900 Mainframe, communication is usually possible by directly
connecting the appropriate interface lines from the SIM928 DB–15
plug to the RS-232 serial port of a personal computer.
2
Connect RXD
from the SIM928 directly to RD on the PC, TXD directly to TD, and
similarly RTS
→ RTS and CTS → CTS. In other words, a null-modem
style cable is not needed.
2
Although the serial interface lines on the DB-15 do not satisfy the minimum
voltage levels of the RS-232 standard, they are typically compatible with desktop
personal computers
SIM928 Isolated Voltage Source