ESP32_PDP11_FFS - A PDP11/40 with RK05 disk in flash.

This is a modified version of a PDP11/40 emulation at https://github.com/Isysxp/PDP11-on-the-M5-Core
This app requires an ESP32 processor with at least 512K of PSRAM.
The current build is targeted for the Adafruit QT Py ESP32-S3 board.
This provide a complete PDP11/40 with an OS on a board the size of a postage stamp!
https://learn.adafruit.com/adafruit-qt-py-esp32-s3/overview
The build enviroment is for the current Arduino IDE V 2.3.1 or the VisualMicro plugin for Visual Studio.
The critical libraries required are:
ESPTelnetStream (https://github.com/LennartHennigs/ESPTelnet)
and Espressif Arduino-esp32 (https://github.com/espressif/arduino-esp32) V 2.0.17.
Disk images: I have included a 'reasonably' complete build of RT11 V5.03 on an RK05 image.
This can be loaded into the Flash File System as a FAT image. The upload tool can be found
in either Arduino IDE 1.8 or via the VisualMicro plugin for Visual Studio.
The app provides 1 telnet stream linked to a DL11 serial port mapped at 2 Unibus addresses: 0775610 and 0776500 Vector:0300.
(Do not try to use both at once!)

Ian Schofield April 2024

Note: With refernce to the flash partition table (Should be set to No OTA 1MB app 3MB flash).
Using ESP-IDF release >= 3.0 results in an app size > 1048576 bytes. This will overflow the app flash.
Please use ESP-IDF release 2.0.17 to correct this error.

Ian Schofield August 2024