Sunday ZOOM ... Got a question? Got an idea to discuss?

[Walt Perko]

Hi, 

We're always open to new ideas, questions, demos, troubleshooting a problem etc.  

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[Walt Perko]

Hi, 

I would like to know the difference between the "PROGRAMMED OUTPUT" and the "STATUS BUS"  ???

also, What is the "PROGRAMMED - INPUT" and "ADDRESS - DATA" ???  

I've only used the toggle switches to STOP - RESET - ADDRESS - DEPOSIT - EXAMINE - and RUN  (What I think are the beginner uses.)  

I see the address I EXAMINE, I see the DATA on the "DATA BUS" ... 

My latest build is hoping to be more helpful in learning and understanding more about the LEDs ... 

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[Terry Fox]

Programmed Output is just the OUTPUT PORT 0xFF.  You can output to port 0xFF, the results will show up on those LEDs - important note: the actual data polarity is backwards.

The STATUS BUS (BYTE) shows the current CPU status bits, from the CPU.

the ADRESS - PROGRAMMED INPUT is a twofer LED.  It can show the upper eight bits of the current address, the upper 8 address switches can also be read by the CPU as INPUT port 0xFF.

 (I used to use this input to select which of three printers I wanted dats sent to, and also allow remote (modem) access or not.)

The ADDRESS - DATA LEDs show the lower eight bits of the address bus.  I don't remember what "DATA" means in relation to those LEDs/switches.  Maybe the CPU Data IN or Data OUT.

I do see another set of "DATA BUS" LEDs right above that. 

Terry