JK microsystems 89-0040, Руководство пользователя

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11
µFlashTCP-EP User’s Manual
JK
microsystems
JP2/3 - COM1 Voltage Levels
These jumpers allow the user to select between RS232 and TTL levels for the COM1 serial port.
Install jumpers on JP2 for TTL levels or JP3 for RS232 levels.
Default position:
JP3: 1-2, 3-4, ..., 13-14, RS232 Levels.
NOTE: Jumpers must not be installed on JP2 and JP3 simultaneously.
JP5 - RS-485 Transmit Enable Select
This jumper selects the processor signal that controls the RS-485 transmit enable. The transmit
enable can be controled either by port 3.5 (short 1-2) or COM2 RTS (short 2-3).
Default position:
2-3, RS-485 transmitter controled by COM2 RTS.
JP6 - Socket Memory Type / Boot Memory Location
This jumper selects the type of memory in the expansion socket. Available choices are SRAM or
Flash. Other memory types may be supported if their pinout is compatible with standard SRAM
or Flash chips. Jumper pins 1-2 and 3-4 for SRAM or pins 1-3 and 2-4 for Flash. This jumper
also allows the board to boot from the expansion socket. This is useful when performing field
updates of the on-board Flash memory or when using an operating system other than DOS.
Jumper pins 5-7 and 6-8 to boot from the on-board memory or jumper pins 7-9 and 8-10 to boot
from the expansion socket.
Default position:
1-3 and 2-4, Flash memory expansion.
5-7 and 6-8, Boot from on-board flash.
Cables and Connectors
Proper cabling is required for optimal performance of the µFlashTCP-EP and for compliance
with EMI and EMC regulations. The following table summarizes the recomended cable type and
length for the various connections.
Shielded cables should be terminated to the µFlashTCP-EP and left floating at the opposite end.
Route interface cables away from power cables and other sources of interference. The chassis
should be connected to an earth ground through one of the mounting screws. Interface cables are
specified for use within a building. If cables are required to connect with outdoor equipment, it is
the customers responsibility to provide approved surge and lightning protection.
The µFlashTCP-EP single board computer is designed to be connected with other devices,
however, good EMC practices must be followed in order to maintain compliance.
Power Unshielded Cable, 18AWG
Max Length: 20m (65.6 ft)
RS-232 Shielded Cable, 20AWG
Max Length: 10m (32.8 ft)
RS-485 Twisted Pair, Shielded, 20AWG
Max Length: 1000m (3280 ft)
Ethernet CAT-5, unshielded twisted pair, 24AWG
Max Length: 100m (328 ft)
Table 2: Cable Specifications
Hardware