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CHAPTER 5 ADVANCED DESIGN EXAMPLES

This chapter contains problems organized in terms of PMS component types. The first set of problems treat the Data operations\D type component. These problems are used as a basis for subsequent sections since they illustrate more complex data operations for binary and binary coded decimal (BCD) data types. Since BCD is so important at the system interface to humans, and also since the internal operations of RTM's and in two's complement binary, it is important to understand both the BCD operations and binary-BCD conversion operations.

The next set of problems in the chapter describes systems in which time is the primary constraint. The encoding and decoding of information as a function of time underlies these systems. Two problem classes are presented: waveform generators (synthesizers) and event per unit time (EPUT) counters (analyzers). Subsequent problems give more complex systems for analyzing various waveforms. One such system records the histogram (distribution) of input samples; this system is functionally a compound DM since data operations and memory are central to it. Another system, the DM(coating thickness monitor) problem is similar to the histogram. The two system synchronization problem is illustrated in the time-based systems using an extended RTM, called the K(arbiter). The arbiter allows two independent control sequences to enter a common control, K(arbiter), in which one control sequence only is permitted to emerge at a time. In this way multiple independent systems can share common facilities in a co-ordinated way.

The Transducer section has four complete problem-examples which are also involved with timing and synchronization. Transducers by their function are interfaces between two systems - an inherent synchronization problem. The first problem considers various methods of digital communication via the telephone network An analog sampling unit at the end of a communication link is then presented. Next an interface to a paper tape punch is given. Finally, T(Teletrola), a device which .uses the data communication format of the ASCII code Teletype to produce a four-octave range of square wave tones is given. With Teletrola, any computer with Teletype output can easily synthesize music- like sounds.

Next, two controls\K are given. One control is for solving abstract problems, using the Turing Machine formulation. A Turing Machine tape transport (with infinite tape) is postulated as an "extended" RTM. Several Turing machine problems are solved for smaller (i.e., 16-cell) tape units. The other problem is concerned with the control of a conveyor which has a number of output stations. As items enter the conveyor a record of them is stored in the control, and then as they move along on the conveyor, they are ejected into the correct output station.

The final section presents three functionally different kinds of memories which use a conventional M(array): the queue, stack, and content addressable. Each is used in a particular way, according to function.

DATA OPERATIONS SUBPROCESSES

INTRODUCTION

This section is concerned with the design of subprocesses, i.e. macros and subroutines, that perform operations on data held in RTM memories. The data 'operation subprocesses are generally necessary because they provide the ability to perform operations not available in RTM's, like multiplication, division, and/or

 

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