Python Peripherals

Python Peripherals

Renode's PythonPeripheral lets you implement a peripheral entirely in Python — useful for custom sensors, mock devices, or anything not covered by the built-in catalog. TypeNode exposes this as Peripherals.Python.pythonPeripheral().

Options

Peripherals.Python.pythonPeripheral({
  $at:       number,           // bus address
  $size?:    number,           // range size (emits <addr, +size>)
  $parent?:  string,           // defaults to "sysbus"
  size:      number,           // memory-mapped size of the peripheral (bytes)
  initable?: boolean,          // whether Renode calls Init() on the peripheral
  script?:   string,           // inline Python script
  filename?: string,           // path to an external .py file
  connections?: Array<{ from?: string; to: string }>,
  extra?:    Record<string, string | number | boolean | { ref: string }>,
})

Provide either script (inline) or filename (external file) — not both.

---

Inline script

Embed the Python directly in your machine description:

import { defineMachine } from "@typenode/core";
import { Peripherals } from "@typenode/peripherals";

export default defineMachine({
  name: "my-board",
  peripherals: {
    // ... cpu, flash, sram ...

    sensor: Peripherals.Python.pythonPeripheral({
      $at:  0x40010000,
      $size: 0x100,
      size:  0x100,
      script: `
if request.isRead:
    request.value = 0xAB
`,
    }),
  },
});

---

External Python file

Keep the script in a separate .py file and reference it by path:

sensor: Peripherals.Python.pythonPeripheral({
  $at:      0x40010000,
  $size:    0x100,
  size:     0x100,
  filename: "peripherals/sensor.py",
}),

sensor.py:

if request.isRead:
    if request.offset == 0x00:
        request.value = 0x42   # STATUS register
    elif request.offset == 0x04:
        request.value = 0x1234 # DATA register
elif request.isWrite:
    self.NoisyLog(f"Write to offset 0x{request.offset:02x}: 0x{request.value:x}")

Paths are passed through to Renode as-is — use absolute paths or paths relative to where you run typenode.

---

Renode Python peripheral API

Inside the script, Renode provides these globals:

Name	Description
request.isRead	True for read access
request.isWrite	True for write access
request.offset	Byte offset within the peripheral's address range
request.value	On read: set this to return a value. On write: the value being written
request.type	Access type (ByteAccess, WordAccess, DoubleWordAccess)
self.NoisyLog(msg)	Log at NOISY level
self.Log(level, msg)	Log at a specific level

---

With IRQ connections

Python peripherals can fire interrupts like any other peripheral:

irqDevice: Peripherals.Python.pythonPeripheral({
  $at:  0x40020000,
  $size: 0x10,
  size:  0x10,
  connections: [{ to: "nvic@5" }],
  script: `
if request.isWrite and request.offset == 0:
    self.IRQ.Set()
`,
}),

---

initable

When initable: true, Renode calls the peripheral's Init() function at startup — useful for one-time setup logic:

sensor: Peripherals.Python.pythonPeripheral({
  $at:      0x40010000,
  size:     0x100,
  initable: true,
  script: `
def Init():
    self.state = 0

if request.isRead:
    request.value = self.state
`,
}),