When Heritage / 1 exists as hardware (May 2010), it's time to start writing software for it. But how software is written for a proprietary platform? Because conventional generating system development Code for a specific operating system and / or specific CPU, not for a newborn and unique environment that no one has heard.
An alternative is to write everything down into machine code, but in this way can not go very far. Another option is to write one of their own development tools, but this is a project in itself, much more complex than the software to be written later.
Fortunately there are tools for this task, both commercial and Open Source, and here we get into the world of assemblers "Forward" (retargetable) and the task of "carrying" a source platform to another.
Assume that we have solved that problem, so now we can write assembly code and generate binary files that the CPU Heritage / 1 to run. This development we do using a PC, of \u200b\u200bcourse, the resulting binary files are forwarded to the memory of Heritage / 1 ... somehow. A BRAIN
initially empty
One of my premises for the design of Heritage / 1 has been that the Software is something "outside" the computer. This implies that H1 has no memory ROM or other medium for storing a program started. When the computer boots up, nothing happens beyond a hardware reset, the computer wakes with zero intelligence.
The software resides as in "storage" (possibly V-TAPES) but to deliver it to memory a program is needed to start or "Loader" (magazine). This program is really small and goes through the console, word for word, bit by bit (it is the task of the operator every morning to his arrival in the calculation). Once into the loader, the operator presses the START button with which the CPU starts to execute. And running, the Loader is responsible for loading the OS from a V-TAPE previously placed in your reader. With the operating system loaded and running, Heritage / 1 have won the necessary intelligence to begin his work useful.
FIRST STEP: BATCH PROCESSING
Hopefully tezón and patience, an operating system itself will appear in due course. But there will be an initial period of experimentation, of course, where all my programs will be entered directly into memory, bit by bit, using the Console. In these circumstances I shall create my access to "storage" and / or (maybe) to a serial port in order to provide a pathway for entry into large software memory from an external medium such as a PC or a V-TAPE. Once this foundation raised, I will be able to build a software system more or less serious.
development
My plan is to make Heritage / 1 cross staggered certain "historical stages" in terms of mode of operation is concerned.
History teaches us that for a decade (1950s) computers worked only in batch mode. This refers to the ability of a computer to run several programs in cascade, one after another, without human intervention between the end of one and pulled the next.
Today we seem to "batch" is the opposite of "interactive", but at the time of its introduction (early 50s), "batch processing" represented an alternative to having to stop the machine every time a program to end and taking the time to prepare for the next program. The batch process achieved catkins overall efficiency of the machine to minimize the cost of downtime CPU. A computer like
Heritage / 1 could serve in a data center in those days, operating in batch mode. Instead of users, professional traders would, and instead of operating system, a simple program "Monitor" charge to read the specifications of the programs to run and manage their load and run automatically in response to priorities and resource availability.
True Heritage / 1 will therefore have the "Batch Monitor" and operate in batch mode for some time. Will this be the time to refine programming techniques and (no doubt) make adjustments to the hardware of the CPU and peripherals.
Then comes a stage much more interesting: Multiprocessing, but more of that in a separate article, given the size of the item.
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