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move documentation to pages
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TomNisbet committed Nov 11, 2023
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2 changes: 1 addition & 1 deletion docs/_docs/100-design.md
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Expand Up @@ -50,7 +50,7 @@ Reset-mode addressing is accomplished with a combination of hardware and softwar
![Reset Trace](images/reset-trace.png)
The image above shows the reset jump circuit in action, as captured by the excellent [Saleae Logic Analyzer](http://www.saleae.com). The numbers shown above the Read line are a decode of address lines A0..A7.

The [Debugging page](docs/debugging) has notes on debugging with a logic analyzer.
The [Debugging page](debugging) has notes on debugging with a logic analyzer.

The trace begins with the processor in reset, which has caused the reset flip-flop's output (Reset FF Q) to go high. As the processor comes out of reset (seen by Reset Out falling), _ROMEN_ is asserted due to the Reset flip flop. The first instruction read from ROM is a 3 byte jump instruction to F000. This is read from the beginning of the ROM, which would normally be at address 8000, although the processor's PC is actually at 0000. After the jump, _A15_ goes high, clearing the flip flop. At this point, RAM and ROM are now addressed normally, using _A15_ low and high, respectively.

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10 changes: 5 additions & 5 deletions docs/_docs/200-build.md
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Expand Up @@ -45,15 +45,15 @@ Also connect the following:
* EEPROM _CE_ to _GND_ (this maps the ROM base address at both 0000 and 8000)
* _RESET_IN_ to _+5V_ through a 10K resistor and also to _GND_ through a pushbutton

Burn the [ROM LED test program](/docs/code#test2a-rom-ledasm) into the EEPROM at starting address 0000H. Note that this program starts with a _JMP_ instruction to clear the reset flip-flop. This isn't needed, but means that the program will also work if the final address decoding hardware is installed.
Burn the [ROM LED test program](code#test2a-rom-ledasm) into the EEPROM at starting address 0000H. Note that this program starts with a _JMP_ instruction to clear the reset flip-flop. This isn't needed, but means that the program will also work if the final address decoding hardware is installed.

If the test above suceedes, basic ROM wiring has been verified. A [second test program](/docs/code#test2b-rom-addressasm) can now be run to verify that all of the upper ROM address lines have been connected correctly. It will flash the LED at different speeds for a successful test or do a continuous fast blink on failure.
If the test above suceedes, basic ROM wiring has been verified. A [second test program](code#test2b-rom-addressasm) can now be run to verify that all of the upper ROM address lines have been connected correctly. It will flash the LED at different speeds for a successful test or do a continuous fast blink on failure.

### Step 3: Serial Communications

[![rom serial schematic](images/step3-rom-serial-sch-360.png)](images/step3-rom-serial-sch.png)[![rom serial build](images/step3-rom-serial-360.jpg)](images/step3-rom-serial.jpg)

The next test, with the same basic hardware, was to wire in the FTDI chip to the SOD and bit-bang a character out as async serial data. The [ROM serial test program](/docs/code#test3-rom-serialasm) writes a continuous stream of the 'T' character to the serial port.
The next test, with the same basic hardware, was to wire in the FTDI chip to the SOD and bit-bang a character out as async serial data. The [ROM serial test program](code#test3-rom-serialasm) writes a continuous stream of the 'T' character to the serial port.

* connect an FTDI interface to _GND_, _SID_ and _SOD_ as shown in the final schematic

Expand Down Expand Up @@ -81,9 +81,9 @@ Also connect the following:
* RAM _CE_ to *inverted* 8085 _A15_ (this maps the RAM base address at 8000)
* complete the reset circuit with the addition of the inverters, capacitor, and diode

The [RAM serial test program](/docs/code#test2a-rom-ledasm) writes a continuous string of A to Z characters to the serial port.
The [RAM serial test program](code#test2a-rom-ledasm) writes a continuous string of A to Z characters to the serial port.

Now that RAM is working, code development can be sped up with the use of the [Hex Loader](/docs/code#loaderasm). This can be burned into the ROM and will load and execute programs from RAM. While not as powerful as a full monitor, it does remove the need to power down the system and remove the ROM for each code update. It accepts Intel Hex files from [asm85](https://github.com/TomNisbet/asm85) or other tools that write in the standard format.
Now that RAM is working, code development can be sped up with the use of the [Hex Loader](code#loaderasm). This can be burned into the ROM and will load and execute programs from RAM. While not as powerful as a full monitor, it does remove the need to power down the system and remove the ROM for each code update. It accepts Intel Hex files from [asm85](https://github.com/TomNisbet/asm85) or other tools that write in the standard format.

### Step 5: Memory Addressing

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