/tt02-davidsiaw-stackcalc

TinyTapeout 2 submission: Stack based calculator

Primary LanguagePythonApache License 2.0Apache-2.0

David's Stack Calculator

This TinyTapeout submission is a 4-bit stack calculator.

スクリーンショット 2022-12-26 10 49 35

Features:

  • 8-nibble deep stack
  • 16 nibbles of RAM
  • multiply/divide circuit
  • fully writable output

diff

Links

Pinouts

  • io_in[0] clock (c)
  • io_in[1] reset (let the clock tick a few times while reset is high)
  • io_in[5:2] Inputs (opcodes and input go here)
  • io_in[6:7] output mode
  • io_out[7:0] output depends on the Output Mode (not clocked)

Opcodes

It implements the following opcodes

  • 0x1 PUSH - 3 cycles - push, value, wait
  • 0x2 POP - 3 cycles - pop, wait, wait
  • 0x3 OUTL - 2 cycles - outl, wait
  • 0x4 OUTH - 2 cycles - outh, wait
  • 0x5 SWAP - 3 cycles - swap, wait, wait
  • 0x6 PUSF - 3 cycles - peek/dupl/flag, wait, wait
  • 0x7 REPL - 3 cycles - not/neg/incr/decr/shr1/shl1/ror1/rol1, wait, wait
  • 0x8 BINA - 3 cycles - add/and/not/xor/addc/mull/mulh, wait, wait
  • 0x9 MULT - 4 cycles - mult, wait, wait, wait
  • 0xA IDIV - 4 cycles - idiv, wait, wait, wait
  • 0xB CLFL - 2 cycles - clfl, wait, wait, wait
  • 0xC SAVE - 4 cycles - save, wait, wait, wait
  • 0xD LOAD - 4 cycles - load, wait, wait, wait

Output Modes

  • 0x0 output register
  • 0x1 top of stack as 7segment
  • 0x2 below top of stack as 7segment
  • 0x3 top two values on the stack, top of stack is low nibble and below is high nibble

FPGA Testing

You can test the design yourself if you do not have the ASIC, by using an FPGA. Currently I only test on a cheap GOWIN FGPA, the Tang Nano 9k.

You will need docker installed.

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FPGA Test commands

make gowin

If you already have the Tang Nano 9k connected and can use openFPGALoader, you can go

make upload_gowin

What is Tiny Tapeout?

TinyTapeout is an educational project that aims to make it easier and cheaper than ever to get your digital designs manufactured on a real chip!

Go to https://tinytapeout.com for instructions!

How to change the Wokwi project

Edit the info.yaml and change the wokwi_id to match your project.

How to enable the GitHub actions to build the ASIC files

Please see the instructions for:

How does it work?

When you edit the info.yaml to choose a different ID, the GitHub Action will fetch the digital netlist of your design from Wokwi.

After that, the action uses the open source ASIC tool called OpenLane to build the files needed to fabricate an ASIC.

Resources

What next?