Delta Tau PMAC2A-PC/104 - Manual (Page 25)

PMAC2A PC104 Hardware Reference Manual
Machine Connections 19
Serial Port (JRS232 Port)
For serial communications, use a serial cable to connect your PC's COM port to the J8 serial port
connector present on the PMAC2A PC/104 baseboard. Delta Tau provides the Acc-3L cable for this
purpose that connects the PMAC to a DB-9 connector. Standard DB-9-to-DB-25 or DB-25-to-DB-9
adapters may be needed for your particular setup. If a cable needs to be made, the easiest approach is to
use a flat cable prepared with flat-cable type connectors as indicated in the following diagram:
1 1
DB-9 Female DB-9 Male
PMAC (DB-9S) PC (DB-9)
1 (No connect) 1 (No connect)
2 (TXD/) 2 (RXD)
3 (RXD/) 3 (TXD)
4 (DSR) 4 (DTR)
5 (Gnd) 5 (Gnd)
6 (DTR) 6 (DSR)
7 (CTS) 7 (RTS)
8 (RTS) 8 (CTS)
9 (No connect) 9 (No connect)
Acc-2P Ethernet RJ45 Connector (J10 Port)
This connector is used for Ethernet communications from the Acc-2P to a PC, and it is provided when
Acc-2P Option 1B is ordered. The PC must have a card dedicated solely to the PMAC network. The
appropriate Category 5 10/100-Base T network cable that mates to this connector can be readily
purchased from any local computer store. The type of network cable to purchase depends on the
configuration to the host PC.
When making a direct connection to a Host communication Ethernet card in a PC a cat 5 networking
crossover cable must be used. A standard cat 5 straight through networking cable cannot be used in this
scenario. When using a connection to a network hub or switch, the standard cat 5 straight through
networking cable must be used, and not a crossover cable.
Performance can be degraded seriously by the use of a hub or switch. Network hubs or the more
intelligent network switches have processors inside them, which can add delays of at least 15msec to the
PMAC communications.
Acc-2P USB Connector (J1 Port)
This connector is to be used in conjunction with USB A-B cable, which can be purchased from any local
computer store, and it is provided when Acc-2P Option 1A is ordered. The A connector is connected to a
PC or Hub device; the B connector plugs into the Acc-2P J1 port.