gHashTag · Oct 19, 2026 · Oct 19, 2026 · Oct 19, 2026 · Oct 19, 2026 · Oct 19, 2026
@@ -63,7 +63,7 @@ <h1>t27 basics: the language in 27 lessons</h1>
 <p class="goal">Before the FPGA course: what a t27 spec is, how the compiler reads it, and what it gives back. Every lesson opens one table or diagram drawn from its own spec and one spec you can run in your browser.</p>
 <p>Course 0, 27 lessons, one infographic and one t27 spec each: a module, constants and types, functions and tests, then the compiler's stages and the 7 languages it writes. It comes before the FPGA course.</p>
 <p><a class="cta" href="/#/t27-basics">Open the interactive course →</a></p>
-<ol class="courses"><li aria-current="page"><a href="/learn/">t27 basics: the language in 27 lessons</a></li><li><a href="/learn/course/">From zero to a chip: FPGA programming with t27</a></li><li><a href="/learn/ai-numbers/">AI numbers with t27: from number formats to a ternary network</a></li><li><a href="/learn/goldenfloat/">GoldenFloat with t27: one rule, seventeen float widths</a></li><li><a href="/learn/verify-hardware/">Verifying hardware with t27: testbenches, waveforms, formal, mutation</a></li><li><a href="/learn/clocks-and-cdc/">Clocking, resets and clock-domain crossings with t27</a></li><li><a href="/learn/buses-and-peripherals/">Buses and peripherals with t27: UART, SPI, APB, AXI4, Ethernet</a></li><li><a href="/learn/ternary-computing/">The ternary machine: from a trit to a running program</a></li><li><a href="/learn/arithmetic-and-dsp/">Arithmetic and DSP on the FPGA: from the carry chain to a filter</a></li><li><a href="/learn/neural-networks/">Neural networks in t27: from one neuron to a transformer block</a></li></ol><nav class="pager"><span></span><a class="chain" href="/learn/course/">Next course: From zero to a chip: FPGA programming with t27 →</a></nav>
+<ol class="courses"><li aria-current="page"><a href="/learn/">t27 basics: the language in 27 lessons</a></li><li><a href="/learn/course/">From zero to a chip: FPGA programming with t27</a></li><li><a href="/learn/ai-numbers/">AI numbers with t27: from number formats to a ternary network</a></li><li><a href="/learn/goldenfloat/">GoldenFloat with t27: one rule, seventeen float widths</a></li><li><a href="/learn/verify-hardware/">Verifying hardware with t27: testbenches, waveforms, formal, mutation</a></li><li><a href="/learn/clocks-and-cdc/">Clocking, resets and clock-domain crossings with t27</a></li><li><a href="/learn/buses-and-peripherals/">Buses and peripherals with t27: UART, SPI, APB, AXI4, Ethernet</a></li><li><a href="/learn/ternary-computing/">The ternary machine: from a trit to a running program</a></li><li><a href="/learn/arithmetic-and-dsp/">Arithmetic and DSP on the FPGA: from the carry chain to a filter</a></li><li><a href="/learn/neural-networks/">Neural networks in t27: from one neuron to a transformer block</a></li><li><a href="/learn/queen-and-hive/">The Queen and the hive: how the t27 project builds itself</a></li></ol><nav class="pager"><span></span><a class="chain" href="/learn/course/">Next course: From zero to a chip: FPGA programming with t27 →</a></nav>
 <section><h2>All lessons</h2><ul class="outline"><li><h3>Module 1 · A spec file</h3><p>What a .t27 file holds: a module line, prose lines and comments.</p><ol><li><a href="/learn/what-a-spec-is/">01 What a spec is</a></li><li><a href="/learn/the-module-line/">02 The module line</a></li><li><a href="/learn/comments-and-prose/">03 Comments and prose lines</a></li></ol></li><li><h3>Module 2 · Values and types</h3><p>Constants, the width of a whole number, and true, false and text.</p><ol><li><a href="/learn/constants/">04 Constants</a></li><li><a href="/learn/whole-numbers/">05 Whole numbers and their widths</a></li><li><a href="/learn/true-false-and-text/">06 True, false and text</a></li></ol></li><li><h3>Module 3 · Arrays, trits and expressions</h3><p>Lists of values, the three values of a trit, and what operators compute.</p><ol><li><a href="/learn/arrays/">07 Arrays</a></li><li><a href="/learn/trits/">08 Trits: minus one, zero, one</a></li><li><a href="/learn/expressions/">09 Expressions</a></li></ol></li><li><h3>Module 4 · Tests and functions</h3><p>A test block, several small tests in one spec, and a function with typed inputs.</p><ol><li><a href="/learn/a-test-block/">10 A test block</a></li><li><a href="/learn/many-tests/">11 Many tests in one spec</a></li><li><a href="/learn/functions/">12 Functions</a></li></ol></li><li><h3>Module 5 · Inside a function</h3><p>Names with let and var, choices with if and switch, and loops.</p><ol><li><a href="/learn/local-names/">13 Local names: let and var</a></li><li><a href="/learn/if-and-else/">14 Choices: if, else and switch</a></li><li><a href="/learn/loops/">15 Loops: while and for</a></li></ol></li><li><h3>Module 6 · Visibility and your own types</h3><p>What pub shares with other modules, and the structs and enums you declare.</p><ol><li><a href="/learn/pub-or-private/">16 pub or private</a></li><li><a href="/learn/structs/">17 Structs</a></li><li><a href="/learn/enums/">18 Enums</a></li></ol></li><li><h3>Module 7 · Modules, rules and gen-ts</h3><p>Reading another module, stating a rule that always holds, and a spec turned into TypeScript.</p><ol><li><a href="/learn/use-other-modules/">19 Using other modules</a></li><li><a href="/learn/invariants/">20 Invariants and benches</a></li><li><a href="/learn/gen-ts/">21 gen-ts: a spec becomes TypeScript</a></li></ol></li><li><h3>Module 8 · The compiler and tri</h3><p>The backends t27c writes, the stages it reads a spec in, and the tri command.</p><ol><li><a href="/learn/seven-backends/">22 Seven backends</a></li><li><a href="/learn/stages-of-t27c/">23 The stages of t27c</a></li><li><a href="/learn/tri-commands/">24 tri: the command line</a></li></ol></li><li><h3>Module 9 · Errors, a program, what next</h3><p>Reading a compiler error, one small complete program, and the course to take next.</p><ol><li><a href="/learn/reading-errors/">25 Reading compiler errors</a></li><li><a href="/learn/a-small-program/">26 A small complete program</a></li><li><a href="/learn/where-next/">27 Where to go next</a></li></ol></li></ul></section>
 <footer><p><a href="/learn/t27-basics.t27">This course is itself a t27 spec: read it</a></p><p>Widgets keep their own English words: each one lives in its own t27 spec.</p></footer>
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