CPU of the Day: UTMC UT69R000: The RISC with a Trick
UTMC UT69R000-12WCC 12MHz 16-bit RISC -1992
We’ve beforehand covered several MIL-STD-1750A appropriate processors in addition to the historical past and design of them. As a reminder the 1750A normal is an Instruction Set Structure, specifying precisely what directions the processor should help, and the way it ought to course of interrupts and many others. It’s agnostic, that means it doesn’t care. how that ISA is carried out, a designers can implement the design in CMOS, NMOS, Bipolar, or the rest wanted to satisfy the bodily wants, so long as it may well course of 1750A directions.
At this time we’re going to have a look at the results of that by a processor that ISN’T a 1750A design. That processor is a 16-bit RISC processor initially made by UTMC (United Applied sciences Microelectronics Middle). UTMC was primarily based in Colorado Springs, CO, and initially was fashioned to deliver a semiconductor arm to United Expertise, together with their acquisition of Mostek, which later was bought to Thomson of France. After promoting Mostek, UTMC focussed on the navy/excessive reliability marked, making many ASICs and radhard components together with MIL-STD-1553 bus merchandise and 1750A processors. The UT69R000 was designed within the late 1980’s to be used in navy and house functions and is a reasonably basic RISC design with 20 16-bit registers, a 32-bit Accumulator, a 64K knowledge house and a 1M tackle house. Internally it’s constructed round a 32-bit ALU and might course of directions in 2 clock cycles, leading to 8MIPS at 16MHz. The 69R000 is constructed on a 1.5u twin-well CMOS course of that’s designed to be radiation hardened (this isn’t your regular PC processor afterall). In 1998 UTMC bought its microelectronics division to Aeroflex, and immediately, it’s a part of the English firm Cobham.
UTMC UT1750AR – 1990 RISC primarily based 1750A Emulation
UTMC additionally made a 1750A processor, often called the UT1750AR, and for those who may marvel why the ‘R’ is added on the finish. The ‘R’ denotes that this 1750A has a RISC mode out there. If the M1750 pin is tied excessive, the processor works as a 1750A processor, tied low, it runs in 16-bit RISC mode. How is that this doable? As a result of the UT1750AR is a UT69R000 processor internally. Its the identical die contained in the package deal, and the pinout is sort of the identical (internally it might be however that’s exhausting to inform). To ensure that the UT1750AR to work as a 1750A it wants an 8Kx16 exterior ROM. This ROM (equipped by UTMC) consists of translations from 1750A directions to RISC macro-ops, not not like how modern-day processors deal with x86. The processor receives a 1750A instruction, passes it to the ROM for translation, after which processes the lead to its native RISC directions. There’s after all a efficiency penalty, processing code this manner ends in 1750A code execution charges of 0.8MIPS at 16MHz, a 90% efficiency hit over the native RISC. For comparability sake, the Fairchild F9450 processor, additionally a 1750A appropriate CPU, executes round 1.5MIPS at 20MHz (clock for clock, about 30% sooner), and thats in an influence hungry Bipolar course of, so the RISC translation isn’t horrible for many makes use of.
NASA Aeronomy of Ice within the Mesosphere – Digital camera powered by RISC
By immediately’s requirements, even of house primarily based processors, the UT69R000 is a bit underpowered, however it nonetheless has discovered broad use in house functions. Not as a principal processor, however as a help processor, often supporting tools that must be at all times on, and at all times prepared. One of many extra well-known mission the UT69R000 served on was powering the dual uplink computer systems for the DAWN asteroid mission (which solely this yr ended). It was additionally used on numerous instrumentation on the now retired Area Shuttles. The CPU additionally powered the digital camera system on the (additionally retired) Earth Observing-1 Satellite tv for pc, taking stellar footage of our planet for 16 years from 2000-2017. One other person is the NASA AIM satellite tv for pc that explores clouds on the fringe of house, initially designed to final a pair years, its mission which began in 2007 remains to be going. The
JAXA/ESA Hinode SOLAR-B Observatory
cameras offering the gorgeous footage are powered by the UT69R000. A JAXA/ESA mission often called SOLAR-B/Hinode can be nonetheless flying and working a Solar observing telescope powered by the little RISC processor.
There are lots of many extra missions and makes use of of the UT69R000, discovering all of them is a bit difficult, as not often does a processor like this get any of the press, its nearly at all times the Command/Information Processor, lately issues just like the BAE RAD750, and LEON SPARC processors, however for a lot of issues in house, and on Earth, 16-bits its all of the RISC you want.