Bluetooth is steadily gaining ground in key markets, such as personal computers (PCs) and computer peripherals. For developers hoping to compete in these and other personal wireless-connectivity applications, the Merlin Mobile Bluetooth protocol analyzer from Computer Access Technology Corp. (Santa Clara, CA) may be their most invaluable tool. This unlikely looking precision test

instrument fits into a standard 16-b Type II PC card. Yet it is a full-featured Bluetooth protocol analyzer qualified to Version 1.1 of the Bluetooth standard for piconet protocol testing. Based on the company's larger Merlin protocol analyzer, Merlin Mobile can fit unobtrusively within a Bluetooth piconet, capturing data but without interfering with the operation of the 2.4-GHz piconet. The analyzer displays packets in a hierarchical view, showing all layers of a particular Bluetooth transaction.

The Merlin Mobile measures just 5.3 × 2.1 × 0.4 in. (135 × 54 × 10.5 mm) and weighs only 2 oz. (57 g). It is supplied with a dipole antenna designed for use at 2.4 GHz (see figure), which can be removed for wired connections.

The protocol analyzer employs what the company calls an "air probe" radio interface that allows users to capture and analyze Bluetooth traffic broadcast within a piconet. It can evaluate baseband, LMP, L2CAP, SDP, RECOMM, TCS, and OBEX layers of the Bluetooth protocol stack. It can also provide decoding functions for HDLC, PPP, BNEP, HID, and AT commands, or create custom decoding functions.

An operator simply loads the Merlin Mobile's software into their laptop or PC, then plugs the Bluetooth protocol-analyzer PC card into the appropriate slot on the computer. The analyzer features sophisticated programmable real-time triggering functions and advanced filtering to isolate events of interest from crowded traffic. The display software operates independently of the analyzer hardware, allowing multiple users to evaluate traces. The software works with MS Windows 98, Millennium Edition (ME), 2000, and XP.

Merlin Mobile supports point-to-point and point-to-multipoint piconets. Its precise counter/timer circuitry allows time stamping of events with 100-ns resolution. The radio portion complies with Class 2 operation . Computer Access Technology Corp., 2403 Walsh Ave., Santa Clara, CA 95051-1302; (800) 909-2282, (408) 653-1262, FAX: (408) 727-6622, Internet: