Arduino Nano as CP/M-Compatible Computer

Hot glue gun (generic)

Arduino Nano R3

Soldering iron (generic)

74LS07

Micro SD card deck

STM8S103F3P6

FM24C256

<p ><span >I will begin here with a description of my project </span><strong >cpm4nano</strong><span > - a CP/M-compatible computer based on the Arduino Nano 3.0.</span></p><p >Currently one (!) Arduino Nano (!) in my project:</p><ul ><li >emulates the Intel 8080 processor, 64 KBytes RAM (with two FRAM chips) + 4 FDD with 100 diskettes (with SDHC card);</li></ul><ul ><li >with the  help of the PS/2-UART converter on STM8 allows you to  enter information from the keyboard (allows you to switch English/Russian languages, upper/lower case, enable lock for scrolling text on screen);</li></ul><ul ><li >displays text information on the TV screen (20 rows with 40 cols or 80 cols on two virtual screens, between which you can switch) without jitter (with duplication of information to the PC through serial channel);</li></ul><ul ><li >receives/sends data from/to the PC through serial port via XMODEM;</li></ul><ul ><li >data input/output via magnetic tape or audiofile;</li></ul><ul ><li >loads the OS CP/M and runs its programs (including BASIC, C, ADA, FORTH, LISP, FORTRAN, FOCAL, MINOL).</li></ul><p ><em ><strong >Project</strong></em><span > </span><em ><strong >in</strong></em><span > </span><em ><strong >progress!</strong></em></p><figure><img src=https://projects.arduinocontent.cc/bc65ffb7-b6bd-41c2-b292-ddeeafef9604.png /><figcaption> </figcaption></figure><p >Displaying the font on the TV screen after the redesign and adding symbols of the pseudographics and Russian letters in the KOI-8 encoding: </p><p >LCD TV </p><figure><img src=https://projects.arduinocontent.cc/cb4ad0d8-27a1-4ed4-9e18-801351fc644c.jpg /><figcaption> </figcaption></figure><p >CRT TV</p><figure><img src=https://projects.arduinocontent.cc/2db4ed65-7278-476f-abaa-28e1920be916.jpg /><figcaption> </figcaption></figure><p >For example, the &#34;screenshot&#34; of the TV screen shows the results of the DIR command and the CPU tests:</p><figure><img src=https://projects.arduinocontent.cc/186319a8-f8ab-4006-921e-325599a41263.png /><figcaption> </figcaption></figure><p >The position of the next character when displayed on the TV screen is indicated by a hardware underline cursor:</p><figure><img src=https://projects.arduinocontent.cc/c6c4160a-aaef-4382-b30a-f8f902b3ab68.png /><figcaption> </figcaption></figure><h3 >8080/8085 CPU Exerciser</h3><p >8080/8085 CPU Exerciser from Ian Bartholomew &amp; Frank Cringles successfully completed (screenshot from TV tuner):</p><p ></p><figure><img src=https://projects.arduinocontent.cc/aba30256-d9dd-4d91-895b-172a5baea026.png /><figcaption> </figcaption></figure><p ></p><h3 >VIrtual screens</h3><p >I overcame the limitation of the physical resolution of the video output of my &#34;nanocomputer&#34; (45 columns) in the style of the Osborne 1 portable microcomputer - using two virtual screens.</p><p >The contents of the current virtual screen are stored in video memory (microcontroller RAM), and the contents of another virtual screen are stored in the main memory (I2C chips).</p><p >Screens are located horizontally, the resolution of the virtual screen is 40 columns and 19 lines + 1 status line:</p><figure><img src=https://projects.arduinocontent.cc/b3346fa2-badc-4700-a3a2-2e5ae68600e4.png /><figcaption> </figcaption></figure><p >Thus, virtual screens emulate a physical screen with 80 columns (Osborne emulated a physical screen with 128 columns through overlapping virtual screens with a width of 56 columns).</p><p >Switching modes (physical screen / virtual screens) is carried out from the monitor program.</p><p >Switching between virtual screens is done by the CTRL-O key combination.</p><p >Example:</p><p >left virtual screen</p><figure><img src=https://projects.arduinocontent.cc/86413348-49d5-4d83-a111-9927c5249357.png /><figcaption> </figcaption></figure><p >right virtual screen</p><figure><img src=https://projects.arduinocontent.cc/99e20c87-e291-4b75-bfc4-bc36d9bc83fd.png /><figcaption> </figcaption></figure><h3 >Running game StarTrek (output on CRT TV):</h3><figure><img src=https://projects.arduinocontent.cc/8f72017a-fb04-4a24-a0e6-f20c1f0539a5.png /><figcaption> </figcaption></figure><h3 >BASIC compiler (CBASIC):</h3><p >compilation:</p><figure><img src=https://projects.arduinocontent.cc/7c865163-77df-4f4c-9f1f-e0d5718864f2.png /><figcaption> </figcaption></figure><p >link:</p><figure><img src=https://projects.arduinocontent.cc/b2c03a5c-8d3c-42e5-95bb-7e1fbefa303a.png /><figcaption> </figcaption></figure><p >run:</p><figure><img src=https://projects.arduinocontent.cc/c0388b09-204a-4385-bfcf-b4891cbdee4b.png /><figcaption> </figcaption></figure><h3 >Altair BASIC 8K:</h3><figure><img src=https://projects.arduinocontent.cc/5e379f02-941a-4cf3-8883-bdeb3550fd99.png /><figcaption> </figcaption></figure><h3 >FOCAL interpreter:</h3><figure><img src=https://projects.arduinocontent.cc/95335361-54a8-48e1-9e74-47a9570495e8.png /><figcaption> </figcaption></figure><h3 >Ada compiler:</h3><figure><img src=https://projects.arduinocontent.cc/1684b526-4826-484d-8844-f5dd4c87408c.png /><figcaption> </figcaption></figure><h3 >LISP/80 interpreter:</h3><figure><img src=https://projects.arduinocontent.cc/e6d2f503-e934-43c3-955f-12238d017a5e.png /><figcaption> </figcaption></figure><h3 >Video Demo:</h3><div class="se-component se-video-container __se__float-none" contenteditable="false" style="width: 100%;"><figure style="width: 100%; height: 56.25%; padding-bottom: 56.25%; margin: 0px;"><iframe frameborder="0" allowfullscreen="" src="https://www.youtube.com/embed/Yuq1yEH-WZ8" data-proportion="true" data-percentage="100%,56.25%" data-size="100%,56.25%" data-align="none" style="width: 100%; height: 100%;" data-index="0" data-file-size="0" data-origin="100%,56.25%"></iframe></figure></div><p ><strong >Current state of project:</strong></p><figure><img src=https://projects.arduinocontent.cc/e34757d5-c5bf-487c-9890-6fe1171c647a.jpg /><figcaption> </figcaption></figure><p ><span >Detailed description (in Russian) - </span><a href="https://acdc.foxylab.com/node/76">https://acdc.foxylab.com/node/76</a></p>

Arduino Nano as CP/M-Compatible Computer

cpm4nano - CP/M-compatible computer based on Arduino Nano.