stub for nanoBoot specifics

docs/tools/nanoboot.md

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+[Home](../../index.md) > [Development](../development.md) > [Tools](tools.md) > **nanoBoot format**
+___
+
+# nanoBoot format
+
+!!! warning
+
+	This is **under development**.
+
+***nanoBoot*** is the software protocol that allows to send code (or generic data) to a _Durango_ or any other computer fitted with a **nanoLink** port.
+
+## Principle of operation
+
+### Signals definition
+
+This is a **two-wire interface** (plus _ground_) based on a Synchronous Serial link. The main feature is that _the receiving side needs almost **no additional hardware**_, as it simply repurposes the regular `/IRQ` and `/NMI` _interrupt_ lines for DATA and CLOCK transmission, respectively. Note that, even if this was designed around the 6502 CPU, _it may be applied to almost any CPU_, as long as it has two interrupt lines with different privilege levels.
+
+### Hardware requisites
+
+TBD
+
+### General operation
+
+TBD...