MASIC Products Bring Adaptability To Embedded Systems

Introduction The embedded control market has been traditionally hampered by the inability to update operating parameters and fmware in a simple manner once the embedded system is installed in the field. While the standardization of the hard disk drive and load-and-execute memory hierarchy have simplified this process in the PC or workstation type of products, this approach is not suitable for the embedded systems due to the cost and complexity of the additional components required. E2PROM and Flash EPROM memories have been utilized in the past for this application, but their complex interface requirements and programming algorithms make them impractical in most embedded applications. The basic challenge in adding alterability through software modification is that the majority of the software in an embedded control system is stored in a semiconductor nonvolatile memory, such as a ROM, EPROM, Flash EPROM or E2PROM. Those devices which are alterable, share a common problem in that the process of updating the contents of the device is a programming sequence. As a result, the devices normally require a complex algorithm or extemal support hardware to accomplish the programming step. The Initial Program Load (IPL) is also a programming step, even for the most user friendly alterable nonvolatile memories, the E2PROMs. The SLICW (Self Loading Integrated Code) E2PROM product family solve these problems. The SLIC family concept is acombination of an byte alterable nonvolatile memory specifically designed to serve as a program and/or data memory for a particular microcontroller and embedded fmware routines written in the native code of the microcontroller. The purpose of the fmware routines is to download the applications software through the microcontroller’s Universal Asynchronous Receiver Transmitter WART) either at IPL or at any time one the system has been delivered to the end customer. The SLIC family of devices provide a simple method of updating or changing software in embedded control systems once the systems are in place in customers sites. The actual update mechanism could be through RS-232, modem or RF link.