[HECnet] Task Buillder question

[Steve Davidson]

Part 2

I wrote conditional macros to allow me to run the “OS” under RT-11 as an application. This was the fastest way to debug logic errors. It didn’t do much for the hardware interfaces but it was better than debugging on the actual HW platform. 

-Steve Davidson

SF:iP1

> On Apr 12, 2021, at 16:43, Steve Davidson <steve at davidson.net> wrote:
> 
> When I was a DEC OEM we used RT-11 and LDA format to load our custom “OS”.  It was my first real project as a system developer. Made good money in those days... 😊
> 
> -Steve Davidson
> 
> SF:iP1
> 
>> On Apr 12, 2021, at 16:17, Paul Koning <paulkoning at comcast.net> wrote:
>> 
>> 
>> 
>>>> On Apr 12, 2021, at 4:09 PM, Johnny Billquist <bqt at softjar.se> wrote:
>>> 
>>> Right.
>>> When someone talks about the paper tape system, and absolute loader format, it is without any operating system underneath. It's just bare metal. And the absolute loader is just a simple format that can be read by a small program that you have in memory. It's only purpose is to read in a paper tape with the binary on it, and start that.
>>> 
>>> So there are no system dependecies, there are no addressing issues. It's just actual bytes that will be written to specific addresses in memory, and then a jump to an address, and off it goes.
>>> 
>>> Johnny
>> 
>> BTW, SimH can load abs loader format files directly (with the "load" command).  So you don't even need to feed it the abs loader to execute such programs.
>> 
>>   paul
>> 
>>