Use logicworks.
Posted: Wed Apr 27, 2022 5:59 pm
Use logicworks.
All contemporary general-purpose microprocessors are designed based on a microprogrammed control unit. You are tasked with designing the microprogram for the MOV Reg A, inbus instruction for a microprocessor. You will use a microprogrammed control unit MOV instruction is a two-address instruction. The destination address is Reg A. The source address can be the inbus or Register B. You are tasked with designing only the case where the source address is the inbus, and you can assume that inbus is already selected by the address selection bit (A.S.) The processing hardware design for this instruction is as follows: BUS MUX EP EP SO 10 1- 40 401 B7400 301 Reg 373 ENLA EN ALOEN 18. DZ 07 DS 05 0515 04 0412 D3 03 D2 02 D1 DO on 105 3d B2300 Inbus D4-D7 204 AS 5200 2d 101 100 10 BUS MUX EN_MEN SO 401 B-400 40 301 B2 30 300 201 B1200 2d 101 BO 10 100 Inbus D0-03 The pseudo microprogram is given as follows: Enable the BUS MUX and Rega Latch the output of Rega Disconnect the BUS MUX from Rega Wait The function table of 74xx373 (Rega) is given below: INPUTS OE EN D L H H L H L I. 1. X нх х Output . Q H L Qo Z 1
Microprogrammed Control Unit Schematic Load/Increment Microprogram Counter (MPC) Reset 3 O 1 Z 1 V cc 2 Control Memory (CM) Mux 6 x 12 12 Control Word Register Condition Select Branch Address Control Functions 2 3
Write the microprogram for the Control Unit. Develop the control unit hardware and the processing unit hardware (given above) in LogicWorks and simulate your circuit to verify that it works. Refer to the instructions at the end of this document on how to create a memory module in Logic Works and how to implemento microprogram counter Hints: 1) Determine what control signals you will need to make the hardware work. This will determine the number of control bits necessary. Note that some of the control signals need to be LOW ACTIVE. 2) Determine how many states are required to complete the operation. This will determine the number of memory locations, and hence the number of address bits, necessary. 3) Determine the conditional execution requirements. This will determine the number of condition bits necessary. 4) Determine the control word for each state with condition, branch address and control function bits. 5) Implement your microprogrammed control unit circuit. Instructions on how to create a memory module in LogicWorks and how to implement a microprogram counter are on the next page. 2
How to create the control memory in LogicWorks: Create the control memory by selecting the PROM/RAM/PLA Wizard under the Simulation drop down menu in LogicWorks (see picture below). Ons A A + LED Co Ctil Shitte Cuil-Shutte Ctrl+U Ctrie Chrik Logic Circut. File de View Schematic Smodation Window Help 5724 Single Stop Run DAX Reset Simulation Clear Unknown Show Values Simulation Param Stick Signals.. Trigge... Simulation Option.. Models Test Vectors Add to Timing Add Automatically Add as Group Import Timing Export Timing Print Timing Timing Print Setup Run Batch File Ctrl+Shift-K Garl-Alt+T Ctrl- AF > Chile Ctrl-Shift+1 Ctrl+Shift-P PROM RAMPLA Weard Medel Wizard.. Show Simulator Toolbar 3
Inside the Wizard, select the Programmable Read Only Memory (see picture below) PLA/PROMRAM Construction Wizard Select the Type of Device to Build Selected Device Elected Code New Device PLA-Programmable Logic vay PROM - Programmatie Find Only Memory RAM Random Access Mentory Cancel Select the number of Address Lines needed and Bits per Word (see picture below) and enter the memory contents manually. The number of Address Lines and Bits per Word, i.e. the width of the memory, will depend on the number of control words and the control word width, respectively. Note: Select the 'Enter hex data manually' radio button. PROM Sothesive De Spala Address Lines 4 ats par Word12 Dals Eddy Muld Adele andekame Cuadelom arawhite Enarhsxcala manus Rack Canes You can either insert your microprogram data in the memory, or leave the memory contents blank to insert the microprogram later. The microprogram needs to be written in HEX numbers with spaces between consecutive numbers. 4
Microprogram Counter: You will need to use one of the counters available in the LogicWorks library to implement the Microprogram Counter. Search the component library in the Parts Palette window for the keyword 'counter'. Select the component 'Counter-4 UP WO/EN'. Apply the necessary connections to the counter, as well as the clock, and observe the counter output in simulation mode. 5
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Microprogrammed Control Unit Schematic Load/Increment Microprogram Counter (MPC) Reset 3 O 1 Z 1 V cc 2 Control Memory (CM) Mux 6 x 12 12 Control Word Register Condition Select Branch Address Control Functions 2 3
Write the microprogram for the Control Unit. Develop the control unit hardware and the processing unit hardware (given above) in LogicWorks and simulate your circuit to verify that it works. Refer to the instructions at the end of this document on how to create a memory module in Logic Works and how to implemento microprogram counter Hints: 1) Determine what control signals you will need to make the hardware work. This will determine the number of control bits necessary. Note that some of the control signals need to be LOW ACTIVE. 2) Determine how many states are required to complete the operation. This will determine the number of memory locations, and hence the number of address bits, necessary. 3) Determine the conditional execution requirements. This will determine the number of condition bits necessary. 4) Determine the control word for each state with condition, branch address and control function bits. 5) Implement your microprogrammed control unit circuit. Instructions on how to create a memory module in LogicWorks and how to implement a microprogram counter are on the next page. 2
How to create the control memory in LogicWorks: Create the control memory by selecting the PROM/RAM/PLA Wizard under the Simulation drop down menu in LogicWorks (see picture below). Ons A A + LED Co Ctil Shitte Cuil-Shutte Ctrl+U Ctrie Chrik Logic Circut. File de View Schematic Smodation Window Help 5724 Single Stop Run DAX Reset Simulation Clear Unknown Show Values Simulation Param Stick Signals.. Trigge... Simulation Option.. Models Test Vectors Add to Timing Add Automatically Add as Group Import Timing Export Timing Print Timing Timing Print Setup Run Batch File Ctrl+Shift-K Garl-Alt+T Ctrl- AF > Chile Ctrl-Shift+1 Ctrl+Shift-P PROM RAMPLA Weard Medel Wizard.. Show Simulator Toolbar 3
Inside the Wizard, select the Programmable Read Only Memory (see picture below) PLA/PROMRAM Construction Wizard Select the Type of Device to Build Selected Device Elected Code New Device PLA-Programmable Logic vay PROM - Programmatie Find Only Memory RAM Random Access Mentory Cancel Select the number of Address Lines needed and Bits per Word (see picture below) and enter the memory contents manually. The number of Address Lines and Bits per Word, i.e. the width of the memory, will depend on the number of control words and the control word width, respectively. Note: Select the 'Enter hex data manually' radio button. PROM Sothesive De Spala Address Lines 4 ats par Word12 Dals Eddy Muld Adele andekame Cuadelom arawhite Enarhsxcala manus Rack Canes You can either insert your microprogram data in the memory, or leave the memory contents blank to insert the microprogram later. The microprogram needs to be written in HEX numbers with spaces between consecutive numbers. 4
Microprogram Counter: You will need to use one of the counters available in the LogicWorks library to implement the Microprogram Counter. Search the component library in the Parts Palette window for the keyword 'counter'. Select the component 'Counter-4 UP WO/EN'. Apply the necessary connections to the counter, as well as the clock, and observe the counter output in simulation mode. 5