The Evolution of the Motorola Microprocessor

The Evolution of the Motorola Microprocessor The 6800 o

After seeing the success of Intel's 8-bit 8008 microprocessor, Motorola introduced its first 8-bit microprocessor, the 6800, in 1974. The 6800 became more prevalent due in part to the system oriented support hardware that Motorola introduced with the 6800. The 6800 was competing in the market with the Intel 8080. The 6800 was used in some early home computer kits, the Tektronix 4051 Graphics Computer System and in a microprocessor trainer sold by Heathkit.

The 6809 o

Around 1977, Motorola introduced the 6809, which was an 8-bit processor with certain 16-bit features. The 6809 had two 8-bit accumulators and two 16-bit index registers and stack pointers, which allowed for advanced memory addressing modes. The 6809 was used in the TRS-80 Color Computer sold by Radio Shack beginning in 1980.

The 68000 o

The 68000, introduced in 1979, was Motorola's first 16-bit processor. The 68000 was actually a hybrid 16/32-bit processor in that it has 16-bit data buses but could perform 32-bit calculations internally. By 1984, Motorola had introduced the 68020, which was a true 32-bit processor compatible with the 68000. A processor in the 68000 family was used in the Apple Macintosh, Sun 3 Workstation, Amiga and Atari ST computers. According to the Institute of Electrical and Electronics Engineers, the 68000 was almost chosen over the Intel 8088 for use in the IBM personal computer.

PowerPC o

In 1991, an alliance of Motorola, Apple and IBM created a microprocessor, called the PowerPC, with a reduced instruction set architecture for use in personal computers. The PowerPC was used in Apple Macintosh computers from 1994 to 2006, and in video game consoles and embedded applications, such as automotive devices. The PowerPC can operate in both big-endian and little-endian modes. Big-endian and little-endian refer to the order of bits in a binary number and which end is the big end or little end of the number. The PowerPC architecture has become a standard that's maintained by Power.org and is used primarily in processors for embedded applications.

Motorola Inc. is one of the leading manufacturers ofmicroprocessors. Until the early 1990s, Motorola microprocessors were used in all Apple Macintosh computers and in manyworkstations. Following the development of its 68040 chip in 1989, however, Motorola changed its focus from the 680x0 line of CISCchips to RISC technologies. In 1993, Motorola joined Apple Computer and IBM in designing a new RISC architecture that would form the basis of the next generation of personal computers. This effort culminated in the introduction of thePowerPC architecture in 1994. There are five main chips in the 680x0 family: the 6800, 68020, 68030, 68040 and 68060. Many people refer to them by their last three digits. For example, the "oh-forty" refers to the 68040 chip.

68000 The internal processor was 32-bit, but externally it used a 16-bit interface. It could address up to 16MB of RAM and execute three quarters of a MIPS (Million Instructions Per Second) on an 8MHz machine. The Amiga 1000, 2000 and 500 was clocked at 7.14MHz. Machines that used it A500 A500+ A600

68008 A cheaper version of the 68000 chip, as used in the Sinclair QL. It has a 16-bit CPU, but only an 8-bit data bus. Machines that used it Sinclair QL

68010 A special version of the 68000 chip designed to multitask. The processor acts as if it were a number of 68000 processors for each program running. A few bugs were fixed in the "supervisor" mode. It was also slightly faster than the 68000 due to slight modifications. Machines that used it Available as an upgrade for A500 owners

68012 Fixed a few bugs in the design. Never used on the Amiga.

68020 A full 32-bit version of the 68000 chip. The full 68020 version increased the amount of memory usable up to 4 gigabytes. The EC (Embedded Controller) version present in the A1200 is only able to use a maximum of 16MB RAM. The chip introduced an instruction cache to increase the speed of operations. The EC version found in the A1200 was chosen because it was slightly cheaper as it did not contain cache memory. Motorola originally designed it to be used in video and washing machines! Machines that used it A1200 Some A500, A500+ and A600 accelerators

68030 An upgraded 68020 chip with a larger cache memory. It also added a Memory Management Unit (MMU) and Floating Point Unit (FPU). This allows the computer to use virtual memory. Some accelerators only fit the EC version of this chip which omits the MMU. The clock speed had also been increased to a maximum of 50MHz. An FPU has to be added externally. Machines that used it A3000, A4000/030, some A500, A500+, A600, CD32 and A1200 accelerators

68040 A vast improvement in speed over the 68030. It contained MMU, FPU and larger instruction and data caches builtin. The 25MHz 68040 found in many A4000's gives a performance of 19MIPS. Some A4000 came with a cut down EC version that did not contain the FPU, whilst the LC (Low Cost) version removed both the MMU and FPU. The 68040 chip is the warmest of the 68k family requiring many 040-based A1200's to be raised slightly to increase ventilation.

Machines that used it A4000/040 Some A500, A500+, A1200, and A3000 accelerators

68060 The last in the 680x0 series. This was almost 100 times faster than the 68000 and three times as fast as the 68040. It had a number of advancements over the 68040 such as the fully static design which witched off individual parts of the processor when it was not in use, saving power and creating less heat. The 50MHz 68060 in a Cyberstorm runs at just under 40 MIPS. Machines that used it A4000/60 Some A1200, A4000 accelerators

68070 Not the next generation of processor, but one even slower than the 68000. Although it is compatible with the 68000, it was made by Philips not Motorola. The SCC68070 features two serial ports, a Memory Management Unit (MMU) and a Direct Memory Access (DMA) controller. The only machine to use it is Philips CDi machine. Machines that used it Philips CDi.

68080/200MHz A misunderstanding by many Amiga enthusiasts led to the belief that Amiga International were attempting to persuade Motorola to continue with their 68k series. This was due to comments by Petro Tyschtschenko at the Cologne 1997 show that it would be easier to develop a market if such a processor existed. Machines that used it None