IBM MaxLoader manual Microcontroller

MaxLoader User’s Guide

reprogrammed like EPROMs. These ICs are called erasable programmable logic devices or EPLDs. Internally, they have the same programmable AND- OR-register structures of the PAL and FPLA.

Microcontroller

These devices are CPU's with on-chip EPROM and RAM. They are typically 40 pins and are UV erasable. They have part numbers such as Intel's 8748,8749,8751,8752 etc. A micro-controller is generally a computer-on-a-chip with RAM, ROM, and I/O ports. Microcontrollers are usually used for specific purposes, such as keyboard decoders, printers, clocks, telephones, CD-players, or any other application that requires a small, on-board computer. Microcontrollers are used to take the place of in-circuit logic, as it can be less expensive and take less space. Also, since it is software driven, the device may be updated very easily. Micro-controllers have the ability to use internal as well as external RAM. Also, micro-controller data may be encrypted or otherwise secured to prevent copying of the data or program information. Microcontrollers also have their own instruction set, usually very similar to familiar Microprocessors (such as the 8080 or 8086). The INTEL MCS-51 family features up to 64k each of internal and external memory, 32 I/O lines, interrupts, timers, and bit-addressable RAM. Its instruction set contains 111 instructions. However, for specific purposes, limited versions of the 51 family are available. For instance, the Philips 87c751/87c752 families do not allow external RAM to be used, and have limited I/O channels, etc. However, these devices still allow for data/program encryption and security levels. They are also less expensive than the MCS-51 micro-controllers.

See the help selection under MAIN-MENU COMMANDS for Encryption and Security-bit information.

NOTE: Programming Microchip PIC familyMicrochip PIC series are different from other Microcontrollers in that they have an EPROM area as well as a Configuration Fuse. The Configuration Fuse in the

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