San Jose, CA-based Atmel, who is known for its programmable logic devices (PLDs), has targeted in on the wireless local-area network (WLAN) market through the release of a new media access controller (MAC) for IEEE 802.11 wireless local-area network (WLAN) systems. Based around an ARM7TDMI RISC processor, the AT76C501 VirtualNet single chip controller provides all of the processing and functionality required by the MAC protocol of IEEE 802.11 standard.
According to Atmel, the ARM7 processor is an important ingredient in the new MAC controller. By incorporating this processor, the new controller allows a WLAN device, such as a PCMCIA card, to process 802.11 code on-chip. This allows WLAN devices, especially PCMCIA cards, to better operate with and more easily install in PCs.
In addition to the ARM7 processor, the AT76C501 contains a PCMCIA bus interface unit, a MAC control unit, and a physical attachment interface (PAI). The PAI provides a generic interface that allows a glueless connection to Harris' PRISM direct sequence spread spectrum (DSSS) radio chip set. This interface also allows the chip to also communicate with other baseband processors, therefore, enabling it to connect with other DSSS or frequency hopping spread spectrum (FHSS) radios.
The move to link the new MAC controller to other DSSS and FHSS radio products may have been important for Atmel. Recently, Harris announced the acquisition of Choice Microsystems, a developer of MAC controllers for IEEE 802.11 systems (see WIRELESS/PORTABLE 99Harris Buys CHOICE Microsystems, Launches Signal Processing Solutions). By acquiring Choice, Harris will now offer its own MAC solution for the PRISM chip set designs. Therefore, Atmel may have to find systems not employing the PRISM chip set for this new controller.
To facilitate quick time-to-market and reduce engineering costs, Atmel has developed an entire PCMCIA reference design kit for the new MAC controller. This reference design includes drivers for Windows 95, Windows 98, Windows NT, and Linux operating systems.
The AT76C501 is the first member of application-specific standard processors (ASSPs) that Atmel will target at WLAN applications. This controller is packaged in a 144-pin TQFP. Samples and the reference design are available by contacting your local sales representative.