gnupic: PIC VM and PIC-on-PIC emulation
Subject:
PIC VM and PIC-on-PIC emulation
From:
David McNab ####@####.####
Date:
24 Dec 2004 11:50:55 +0000
Message-Id: <41CC0297.5060508@rebirthing.co.nz>
Hi,
Has anyone written a PIC16Fxxx emulator to run on PIC16Fxxx?
If so, does it support execution of programs residing off-chip, say, in
24LCxxx I2C Serial EEPROM?
And if so, would gpasm or other tools allow assembling of programs
larger than the PIC 16F876/7 8kword limit?
I ask, because I'm experimenting with an on-PIC VM which executes code
resident off-chip within I2C serial EEPROM (24LC256 presently).
This VM is an escape from PIC hardware limitations (eg 8k program size
and 8 return stack). This VM allows n return stack levels and up to 64k
code size.
(Also, the VM contains a bootloader which downloads bytecode program
images and writes them to I2C EEPROM. And, I've got a basic Forth
compiler working which generates bytecode images for the VM).
While writing the VM, it occurred to me that a PIC-on-PIC emulator might
also work as an escape from hardware limits - provided that compilers
can be persuaded to support access to 64k program space.
So if anyone has already written a PIC-on-PIC VM, I'd like to know, so I
don't go reinventing any wheels.
--
Cheers
David
