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processor emulator manual
commands
assemble
summary
Either the ASSEMBLE or COMPILE commands will start storing processor instructions into program memory. For now these two commands have the exact same effect, although this will probably change in the future. This mode can be identified by a > prompt. Commands (as contrasted with assembly language instructions) will be implemented immediately.
There are severe restrictions on the use of the assemble command, documented below. These restrictions are a result of the emulator being in an early state of development and they will eventually be removed, but you need to know these restrictions if you intend to use the emulator now.
processor emulator manual
commands
assemble
Either the ASSEMBLE or COMPILE commands will start storing processor instructions into program memory. For now these two commands have the exact same effect, although this will probably change in the future. This mode can be identified by a > prompt. Commands (as contrasted with assembly language instructions) will be implemented immediately.
There are absurd restrictions on the compile or assemble mode. These restrictions are imposed by the fact that the emulator is still in a very early stage of development. These restrictions will be removed, but it is important to get a reasonable range of functionality before cleaning up these restrictions.
The compile or assemble mode only works correctly for the first processor (processor 0).
The compile or assemble mode places an instruction into the location identified by the current PC. It overwrites any previous contents of that location in program code memory.
The program code memory must start at location zero (0) and fill every consecutive location until the last instruction’s program code memory location.
Once a program code memory lcoation has been filled, it may at any time be overwritten with any other instruction. Use the CHANGE PC location command to prepare to overwrite a previously entered instruction.
You may create a series of NOP instructions to prefill the progtram code memory to guarantee reserving the appropriate space and then place instructions in any order you desire. I will be adding a FILL NOP number to allow you to quickly do this NOP fill.
Instructions are added without evaluating whether they are valid or not. Invalid instructions will fail at execution time. At the moment this will result only in an indication of a bad command or instruction and either no change to the processor state or only a change to the PC value (depending on factors that will be fixed later).
Yes, these are absurd restrictions, but the chocie is to give access to the capabilities already coded or to prevent access to the ability to store a program. For my own testing, I need the ability to store a short program (to test branch, jump, and subroutine instructions as they are implemented), so that decided which choice you get.
contact
If you find this interesting and want to contact me, write to Milo, PO Box 5237, Balboa Island, California, 92662, USA.
if you want to make a tax-deductible donation to the StarTree107 Foundation to support this educational work, contact Dr. Barry at 949-675-5778
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