DIGI PIN ASSIGNMENTS Digi DB-9 Connector Pin Assignments Signal Description DTE Use Pin # GND Chassis Ground N/A Shell DCD Data Carrier Detect Input 1 RxD Received Data Input 2 TxD Transmitted Data Output 3 DTR Data Terminal Ready Output 4 SG Signal Ground Reference 5 DSR Data Set Ready Input 6 RTS Request to Send Output 7 CTS Clear to Send Input 8 RI Ring Indicator Input 9 Note that GND and SG on the DB-9 are connected within the USB module. Digi DB-25 Connector Pin Assignments Signal Description DTE Use Pin # GND Chassis Ground N/A Shell TxD Transmitted Data Output 2 RxD Received Data Input 3 RTS Request to Send Output 4 CTS Clear to Send Input 5 DSR Data Set Ready Input 6 SG Signal Ground Reference 7 DCD Data Carrier Detect Input 8 DTR Data Terminal Ready Output 20 RI Ring Indicator Input 22 CABLE WIRING This section contains the following topics: DB-9 to Modem (DB-25) DB-9 Software Handshaking (DB-25, XON/XOFF) DB-9 Hardware Handshaking (DB-25, Ready/Busy) DB-9 to Modem (DB-25) DB-9 Female DB-25 Male Signal Pin Pin Signal GND Shell --- Shell GND (cable shield) TxD 3 ----- 2 TxD RxD 2 ----- 3 RxD RTS 7 ----- 4 RTS CTS 8 ----- 5 CTS DSR 6 ----- 6 DSR SG 5 ----- 7 SG DCD 1 ----- 8 DCD DTR 4 ----- 20 DTR RI 9 ----- 22 RI To connect to a modem, use a standard "straight-through" cable. DB-9 Software Handshaking (DB-25, XON/XOFF) DB-9 Female DB-25 Male Signal Pin Pin Signal GND Shell --- Shell GND (cable shield) RxD 2 ----- 2 TxD TxD 3 ----- 3 RxD SG 5 ----- 7 SG This simple DB-25 terminal/printer cable is a three-wire null modem cable. Transmitted Data on one end of the cable is connected to Received Data at the other end, and vice versa. The male DB-25 end can be plugged directly into most serial terminals and printers without any adapters. The female DB-9 end plugs directly into one of the DB-9 connectors on the USB module. In most cases, serial terminals and printers need only a three-wire connection. Digi device driver software supports XON/XOFF (software) handshaking, so the only signal lines necessary are Transmitted Data (TxD), Received Data (RxD), and Signal Ground (SG). DB-9 Hardware Handshaking (DB-25, Ready/Busy) DB-9 Female DB-25 Male Signal Pin Pin Signal GND Shell --- Shell GND (cable shield) RxD 2 ----- 2 TxD TxD 3 ----- 3 RxD +-- 4 RTS | +-- 5 CTS SG 5 ----- 7 SG CTS 8 ----- 20 DTR This terminal/printer cable is valid with any Digi DB-9 USB serial port. Most terminals and printers use Data Terminal Ready (DTR) for Ready/Busy hardware handshaking. The cable shown supports this method. (Note that pins 4 and 5 of the DB-25 are connected together.) Some Okidata printers use a control signal on pin 11, called Supervisory Send Data (SSD) instead of DTR. In this case, simply connect CTS on the female DB-25 side to pin 11 of the male DB-25, instead of pin 20. Other printer manufacturers may use different methods of flow control. Consult your printer=92s documentation for specific wiring requirements. GENERAL CABLE INFORMATION This section contains the following topics: Cable Requirements Grounding Requirements Environment Requirements Data Rate Information Transmission Errors Cable Requirements EIA-232 serial interface cables should be shielded, low capacitance cables, ideally designed specifically for serial data transmission. EIA-422 interface cables should be shielded twisted-pair cables. Each signal requires two leads (one twisted pair of wires) to complete a balanced voltage digital circuit. The shield should be connected to the Chassis Ground of the devices at both ends of the interface cable. Grounding Requirements EIA-232 interface cables should have the shield grounded at both ends of the cable. Chassis Ground--available on the shell of Digi=92s DB-9 connectors--is ideal for this purpose. EIA-422 interface cables must provide a ground path between the devices to be connected. This ensures the integrity of data transfers and control signals. This should be connected to the Chassis Ground of each device. Digi recommends using the cable shield for this purpose. Environment Requirements While good shielding provides reasonable protection against "noise" (Electro-Magnetic Interference, or EMI), cables should still be routed away from noise sources wherever possible. Avoid laying cables in close proximity to transformers, generators, motors, fluorescent lights, etc. Data Rate Information The maximum date rate which may be used for EIA-232 connections is primarily determined by the quality and length of the interconnecting cable. The quality of the cable (for transmission purposes) is generally determined by the capacitance per foot rating of the cable. The following table gives the recommended maximum cable length for a given baud rate. Longer cables may be implemented at the user=92s discretion. Baud Rate Max Cable Length 57,600 or less 100 feet 115,200 80 feet 230,400 40 feet 460,800 20 feet 921,600 10 feet The table assumes the following: 1. The maximum length is the amount of cable which may be connected to a Digi supplied interconnect device such as a USB module. 2. Maximum length is based on a cable rated at: 12.3 pF/foot, conductor to conductor 22.4 pF/foot conductor to shield Transmission Errors If transmission errors occur, attempt the following to determine the cause of the problem: 1. Reduce the baud rate. 2. Reduce the cable length. 3. Use a cable with a lower capacitance per foot rating. In situations where low-capacitance cable is unavailable, or very long cable runs are required, "short-haul" modems, available from suppliers such as Black Box, can be used to increase the effective range of the EIA-232 interface. Short-haul modems are similar to standard modems, except that they are connected directly to each other via a cable instead of going through a telephone circuit.Download Driver Pack
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Expand the archive file (if the download file is in zip or rar format).
If the expanded file has an .exe extension, double click it and follow the installation instructions.
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Find the device and model you want to update in the device list.
Double-click on it to open the Properties dialog box.
From the Properties dialog box, select the Driver tab.
Click the Update Driver button, then follow the instructions.
Very important: You must reboot your system to ensure that any driver updates have taken effect.
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