5 SAP-1 Computer

5 : SAP-1 Computer

Design render
  • Author: Brandon Cruz
  • Description: Simple as Possible computer into ASIC
  • GitHub repository
  • Clock: 10000000 Hz

How it works

Originally, Malvino and Brown presented the SAP-1 architecture in a book called Digital Computer Electronics. The design gained massive popularity when it was build as a bread board computer by Ben Eater on a series of YouTube videos. The architecture contains various modules, including

  • Clock
  • Program Counter
  • Register A
  • Register B
  • Adder
  • Memory
  • Instruction Register
  • Bus
  • Controller This design doesn't have inputs, it is dependent only on the clock that coordinates sequence of the computer's operation. Its operation consists on the communication that that bus provides between modules; the signal load dumps information into a module and the enable signal allows the bus to receive a signal. The bus is 8-bit width since it is an 8 bit computer, and the registers are also 8-bit registers. The computer can only perform addition, whether it is positive numbers or negative numbers (substraction). The signals information is stored within the memory module. There bus operations are coordinated with a series of multiplexers and
    the instruction execution set gives the SAP-1 a total of six stages from 0 to 5, repeating all over again. The more important module is the controller. It controlls the assertion execution according to the stimuli from the stages. The stages 3 to 5 five depend on the instructions of the operation codes.

How to test

Design Output Reading Section The design is engineered to read the output signal generated from the bus, which contains the information of the add and subtract operations executed by the design. Currently, the only method to read the signals is through an oscilloscope. However, a significant enhancement would be the implementation of a state machine controlling a 3 7-segment display to show the numbers on the 8-bit bus (up to 255).

External hardware

Oscilloscope

IO

#InputOutputBidirectional
0n/abus[0]n/a
1n/abus[1]n/a
2n/abus[2]n/a
3n/abus[3]n/a
4n/abus[4]n/a
5n/abus[5]n/a
6n/abus[6]n/a
7n/abus[7]n/a

Chip location

Controller Mux Mux Mux Mux Mux Mux Mux Mux Mux Mux Mux Mux Mux Mux Mux Mux Mux Mux Mux Mux Mux Mux Mux Mux tt_um_chip_rom (Chip ROM) tt_um_factory_test (TinyTapeout 05 Factory Test) tt_um_loopback (TinyTapeout 05 Loopback Test Module) tt_um_Leaky_Integrate_Fire_nfjesifb (Leaky Integrate and Fire Neuron Model) tt_um_topModuleKA (Time Multiplexed Neuron Ckt) tt_um_sap_1 (SAP-1 Computer) tt_um_lif (Leaky Integrate-and-Fire Neuron (Verilog Demo)) tt_um_jleugeri_ticktocktokens (TickTockTokens) tt_um_LSNN (Spiking LSTM Network) tt_um_if (Integrate-and-Fire Neuron. (Verilog Demo)) tt_um_mihailocode_neural_network (Neural network on chip) tt_um_hls_lfi (Simple Leaky Integrate and Fire (LIF) Neuron) tt_um_diadatp_spigot_e (e Spigot) tt_um_kskyou (Continued Fraction Calculator) tt_um_wokwi_380005495431181313 (Water Pump Controller) tt_um_EventFilter (Event Denoising Circuit) tt_um_wokwi_380416099936681985 (7 segment seconds (Verilog Demo)) tt_um_freq_hcohensa (Frequency Encoder/Decoder) tt_um_wokwi_380410498092232705 (UART Greeter with RNN Module) tt_um_wokwi_380120751165092865 (WS2812B LED strip driver) tt_um_wokwi_380408486941145089 (Tiny Tapeout 5 Workshop) tt_um_wokwi_380409169798008833 (Tiny Tapeout 1) tt_um_wokwi_380409488188706817 (Supercon Workshop) tt_um_matrix_multiplier (Matrix Multiplier) tt_um_wokwi_380408594272345089 (Clock Divider) tt_um_wokwi_380408784463076353 (Binary Counter) tt_um_wokwi_380408396356749313 (ring osc test) tt_um_7segx4_clock_abhishek_top (7 segment clock with 4 digits) tt_um_wokwi_380409481852161025 (test001) tt_um_hodgkin_huxley (Hodgkin-Huxley Chip Design) tt_um_wokwi_380408823952452609 (Character Selector) tt_um_wokwi_380409904919056385 (Intructouction to PRBS) tt_um_wokwi_380409081067502593 (tto5 Supercon Project) tt_um_jmadden173_delta_modulation (Delta Modulation Spike Encoding) tt_um_wokwi_380409086743445505 (GameOfLife) tt_um_reflex_game (Reflex Game) tt_um_wokwi_380409019830656001 (Logic Gates Tapeout) tt_um_Fiona_CMU (Stream Cipher w/ LSR) tt_um_wokwi_380409532780455937 (tt5modifyd) tt_um_alu_chip (ALU Chip) tt_um_wokwi_380408936929183745 (Tapeout Test) tt_um_rjmorgan11_calculator_chip (Calculator chip) tt_um_wokwi_380409369220404225 (Shifty Snakey) tt_um_synth_GyanepsaaS (Synth) tt_um_wokwi_380408774591779841 (Sawtooth Generator) tt_um_wokwi_380197591775930369 (Blinking A) tt_um_wokwi_380409393770716161 (Supercon 2023) tt_um_mvm (Sparsity Aware Matrix Vector Multiplication) tt_um_wokwi_380408455148316673 (Ring Oscillator and Clock Source Switch) tt_um_mv_mult_alrdelcr (Matrix Vector Multiplication (Verilog Demo)) tt_um_wokwi_380416361853146113 (IDK WHAT TO DO) tt_um_wokwi_379319062779062273 (7-segment display logic system ) tt_um_wokwi_380409568391147521 (Hardware Trojan Example) tt_um_wokwi_379824923824476161 (Analog Clock) tt_um_wokwi_380145600224164865 (7 segment display) tt_um_wokwi_379889284755158017 (W_Li_10/28) tt_um_wokwi_380408409844584449 (Supecon Gate Play) tt_um_manjushettar (ECE 183 - Integrate and Fire Network Chip Design) tt_um_wokwi_380409236812508161 (tto5) tt_um_rebel2_balanced_ternary_ALU (REBEL-2 Balanced Ternary ALU) tt_um_wokwi_380229599886002177 (Stochastic Multiplier) tt_um_jeffdi_seven_segment_seconds (7 segment seconds - count down) tt_um_wokwi_380416616536542209 (TT05 Submission) tt_um_lif_n (Leaky Integrate-and-Fire Neuron) tt_um_wokwi_379764885531576321 (Count via LFSR) tt_um_dlmiles_tt05_i2c_bert (I2C BERT) tt_um_loopback_ericsmi (tt05-loopback tile with input skew measurement) tt_um_flappy_vga_cutout1 (Flappy VGA) tt_um_async_proc_paulschulz (Asynchronous Parallel Processor Demonstrator) tt_um_wokwi_380055891603379201 (Hex Countdown) tt_um_nickjhay_processor (Matrix multiply coprocessor (8x8 1bit)) tt_um_htfab_cell_tester (Standard cell generator and tester) tt_um_wta (Winner-Take-All Network (Verilog Demo)) tt_um_muncherkin_lioncage (Lion cage) tt_um_seven_segment_seconds_ksandov4 (Brain Inspired Random Dropout Circuit) tt_um_seanvenadas (Event-Based Denoising Circuit) tt_um_wokwi_378231665807713281 (RAM cell test) tt_um_rejunity_ay8913 (Classic 8-bit era Programmable Sound Generator AY-3-8913) tt_um_rnn (RNN (Demo)) tt_um_gharenthi_top (STDP Neuron) tt_um_SNN (Basic Spiking Neural Network) tt_um_btflv_8bit_fp_adder (8 bit floating point adder) tt_um_perceptron (Perceptron Hardcoded) tt_um_jkprz (Cheap and quick STDP) tt_um_topLevel_derekabarca (Brain-Inspired Oscillatory Network) tt_um_uwuifier (UART uwuifier) tt_um_perceptron_connorguzi (Perceptron and basic binary neural network) tt_um_hadirkhan10_lif_neuron (Leaky Integrate-and-Fire Neuron) tt_um_wokwi_380119282165535745 (7 segment seconds) tt_um_uabc_electronica_2023 (UABC-ELECTRONICA) tt_um_proppy_bytebeat (bytebeat) tt_um_meriac_play_tune (Super Mario Tune on A Piezo Speaker) tt_um_wrapper_inputblackboxoutput (Byte Computer) tt_um_vhdl_seven_segment_seconds (7 segment seconds (VHDL Demo)) tt_um_cejmu (4-Bit ALU) tt_um_rejunity_sn76489 (Classic 8-bit era Programmable Sound Generator SN76489) tt_um_minipit_stevej (Miniature Programmable Interrupt Timer) tt_um_gchenfc_seven_segment_gerry (7-segment Name Display) tt_um_supertails_tetris (Tetris) tt_um_mabhari_seven_segment_seconds (Simple_Timer-MBA) tt_um_njzhu_uart (UART Receiver) tt_um_wokwi_376553022662786049 (AGL CorticoNeuro-1) tt_um_adaptive_lif (Leaky-Integrated Fire Neuron) tt_um_myuart (MyUART) tt_um_wokwi_380438365946734593 (UART test) tt_um_tkmheart (Heart Rhythm Analyzer) tt_um_stdp (Spike-timing dependent plasticity (Verilog Demo)) tt_um_wokwi_380465686251921409 (Tiny Tapeout 5 TM project1) tt_um_thermocouple (Thermocouple-to-temperature converter (digital backend)) tt_um_wokwi_380412382001715201 (Naive 8-bit Binary Counter) tt_um_asinghani_tinyscanchain_tt05 (tinyscanchain Test Design) tt_um_carlosgs99_cro_udg (6 digit chronometer.) tt_um_suhrojo (Convolutional Network Circuit Chip Design) tt_um_mvm_ (Matrix Vector Multiplication Accelerator) tt_um_perceptron_neuromeme (Perceptron (Neuromeme)) tt_um_czlucius_alu (4 Bit ALU) tt_um_BNNNeuron (Binary Neural Network (Verilog Demo)) tt_um_urish_skullfet (SkullFET) tt_um_ja1tye_sound_generator (Wavetable Sound Generator) tt_um_jaylennee_wta_pwm (PWM signal generation with Winner-Take-All selection) tt_um_joerdsonsilva_top (Multimode Modem) tt_um_toivoh_synth (Analog emulation monosynth) tt_um_tiny_game_of_life (Tiny Game of Life) tt_um_mingkaic1_stack_machine (Stack Machine) tt_um_morningjava_top (ChipTune) tt_um_urish_silife (Game of Life 8x8 (siLife)) tt_um_tt05_analog_test (TT05 Analog Testmacro (Ringo, DAC)) tt_um_wokwi_380409528895479809 (RBUART) tt_um_mattngaw_fp8 (8-bit Floating-Point Adder) tt_um_chip_inventor_music__6_bit_count (6 bit Counter and Piano Music created by Chip Inventor) tt_um_4_bit_pipeline_multiplier (4 Bit Pipelined Multiplier) tt_um_wokwi_380477805171811329 (2-Bit ALU + Dice) tt_um_wokwi_380490286828784641 (TT02 Wokwi 7seg remake) tt_um_wokwi_380361576213660673 (ping pong asic) tt_um_prg (A Boolean function based pseudo random number generator (PRNG)) tt_um_digital_clock_sellicott (Digital Desk Clock) tt_um_haozhezhu_top (4-bit FIFO/LIFO) tt_um_top_mole99 (One Sprite Pony) tt_um_GrayCounter_ariz207 (4 bit Sync Gray Code Counter) tt_um_clkdiv (Clock and Random Number Gen) tt_um_matt_divider_test (TT05 Analog Test) tt_um_tomkeddie_a (VGA Experiments) tt_um_rejunity_rule110 (Rule110 cell automata) tt_um_no_time_for_squares_tommythorn (No Time for Squares) tt_um_urish_silife_max (Game of Life 8x32 (siLife)) tt_um_gfg_development_tros (TROS) tt_um_chatgpt_snn_mtomlin5 (ChatGPT designed Spiking Neural Network) tt_um_ks_pyamnihc (Karplus-Strong String Synthesis) tt_um_dinogame (VGA Dino Game) tt_um_himanshu5_prog_chipTop (Dual Compute Unit) tt_um_rtfb_collatz (Collatz conjecture brute-forcer) tt_um_retospect_neurochip (Field Programmable Neural Array) tt_um_urish_dffram (DFFRAM Example (128 bytes)) tt_um_rejunity_snn (Chonky SNN) tt_um_hh (Hodgkin-Huxley Neuron) tt_um_wokwi_377426511818305537 (PRBS Generator) tt_um_devinatkin_stopwatch (Stop Watch) tt_um_algofoogle_vga_spi_rom (vga_spi_rom) tt_um_blink (RO and counter) tt_um_ttl74hc595_v2 (8-Bit Shift Register with Output Latches 74HC595) tt_um_psychogenic_neptuneproportional (Neptune guitar tuner (proportional window, version b, debug output on bidir pins, larger set of frequencies)) tt_um_urish_simon (Simon Says game) tt_um_kianV_rv32ima_uLinux_SoC (KianV uLinux SoC) tt_um_urish_ringosc_cnt (Ring oscillator with counter) tt_um_sunaofurukawa_cpu_8bit (cpu_8bit) tt_um_vga_clock (VGA clock) tt_um_seven_segment_seconds (7 segment seconds (Verilog Demo)) tt_um_frequency_counter (Frequency counter) tt_um_rgb_mixer (RGB Mixer) tt_um_MichaelBell_spi_peri (SPI Peripheral) tt_um_multiplexed_clock (Multiplexed clock) tt_um_psychogenic_shaman (Shaman: SHA-256 hasher) tt_um_yubex_metastability_experiment (metastability experiment) Available Available Available Available Available Available Available Available Available Available Available Available Available Available Available Available Available Available Available Available Available Available Available Available Available Available Available Available Available Available Available Available Available Available Available Available Available Available Available Available Available Available Available Available Available Available Available Available Available Available Available Available Available Available Available Available Available Available Available Available Available Available Available Available Available Available Available Available Available Available Available Available Available Available Available Available Available Available Available Available Available Available Available Available Available Available Available Available Available Available Available Available Available Available Available Available Available Available Available Available Available Available Available Available Available Available Available Available Available Available Available Available Available Available Available Available Available Available Available Available Available