User`s manual

The Wireless Connectivity Expert

ACT-IR224UN

User’s Manual

Page 6 of 34

Jul 15, 2010

Version 1.2.0

4 SPECIAL NOTICE & SYSTEM REQUIREMENT

4.1 Special Notice

4.1.1. Timing of COM Port Closing

ACT-IR224UN uses DTR and RTS signals to configure IR communication speed and has 256

bytes inbound buffer & 256 bytes outbound buffer. Normally this Raw IR transmitting dongle has

no flow control protocol. So, if the sending side has completed its sending but some data in

dongle buffer still pending transmission before you close the COM port, DTR and RTS signal will

get change consequently. This will also cause the baud rate change. In such a case the receiver

will get junk data. To prevent this, we recommend giving some delay time before closing the port,

which ensures all pending data being sent out completely.

4.1.2. Improve the Throughput

We recommend sending bulk of data rather than byte-by-byte data to achieve good throughput.

E.g., send the entire data as a whole, instead of calling the write API one byte at a time. If your

data size is too big, then you can send them in multiple blocks.

4.2 System Requirement

1. Windows 98/ME/2000 SP4, Win XP SP2/Vista (32 & 64 bit),Win CE, Mac or Linux. For Windows 7

(32 & 64 bit), please use RC build 7100 or above. Windows Server 2003/2008 (32 & 64 bit).

2. At least 256MB RAM (512MB is recommended).

3. Processor Speed 1.8 GHz.

4. USB 1.1 port (or above).

5 FAQ (Frequently Asked Questions)

• Q1: When we use ACT-IR224UN, occasionally at the end of communication, a few bytes show as

junk in receiver side. Why? And how to solve?

• A1

: Please refer to item 4.1.1 “Timing of COM Port Closing” in section 4.1 Special Notice.

• Q2

: How to improve the channel utilization or throughput?

• A2

: Please refer to item 4.1.2 “Improve the Throughput “in section 4.1 Special Notice.

• Q3

: While un-installing the ACT-IR224 Configuration utility or Driver, Windows prompts to Restart. Do

I need to restart the PC?

• A3

: Yes! We highly recommend restarting the PC so that you can complete the un-installation

successfully.

• Q4

: In some Windows XP, while Un-installing ACT-IR224UN driver (from “Add or Remove

Programs”), it is not restarting automatically when I select “Yes” to restart. Why?