2019-07-01 17:33:44 +00:00
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# OF816
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OF816 is a [65C816](https://www.westerndesigncenter.com/wdc/w65c816s-chip.cfm)
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Forth implementation heavily inspired by
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[Open Firmware (IEEE 1275-1994)](https://www.openfirmware.info/Welcome_to_OpenBIOS).
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2020-03-06 06:50:34 +00:00
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Note that OF816 is *not* an Open Firmware implementation (yet), but it has the
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2019-07-01 17:33:44 +00:00
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potential (and groundwork has been done) for it to become one.
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## Features
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Among its many features are:
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* Mostly platform-independent. OF816 can be ported easily to new systems.
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2020-06-22 01:10:25 +00:00
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* Ports currently exist for the following platforms:
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* [WDC W65C816SXB](https://wdc65xx.com/Single-Board-Computers/w65c816sxb/).
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* [Neon816](https://hackaday.io/project/164325-neon816).
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* [Apple IIgs](https://en.wikipedia.org/wiki/Apple_IIGS).
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* [C256 Foenix](https://c256foenix.com) via [this fork](https://github.com/aniou/of816).
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* GoSXB - an unreleased emulator designed for OF816 development.
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2019-07-01 17:33:44 +00:00
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* New ports require the implementation of a handful of routines.
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* Simple instantiation of one or more Forths in a system.
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* 32-bit cells.
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2020-03-09 23:41:53 +00:00
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* ROM-able.
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* The core system does not write outside of data space, except to the 65816
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direct page and stack.
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* System variables are provisioned at the start of data space when the sytem
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is initialized.
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2019-07-01 17:33:44 +00:00
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* Optional [FCode](https://www.openfirmware.info/Forth/FCode) support
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(less Device Tree and Package functions).
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* [ANS Forth](http://lars.nocrew.org/dpans/dpans.htm)
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* Core, most of Core Ext, Exception, Search Order, and Search Order Ext word
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sets.
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* Smattering of words from other sets.
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2020-03-06 06:49:03 +00:00
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* Good conformance test coverage.
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2019-07-01 17:33:44 +00:00
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## Goal
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The goal of OF816 is to help get 65C816-based projects off the ground in terms
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of development and testing. With a little effort it can be brought up on a new
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system and used to play around with new hardware.
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OF816 is not designed for speed. While reasonably performant, the primary goal
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was compatibility with 32-bit Open Firmware's core word set, cell size, and
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FCode. This allows the possibility of re-using existing Forth source and FCode
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to develop hardware drivers, and potentially developing OF816 into a full Open
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Firmware implementation.
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## Resources
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In addition to the links above, please see the ``LICENSE`` file, ``docs\``, and
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the directories under ``platforms\``.
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OF816 is licensed under a two-clause BSD license.
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