Difference between revisions of "RetroComputers"

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[[File:tindie-mediums.png|link=https://www.tindie.com/stores/land_boards/]]
 
[[File:tindie-mediums.png|link=https://www.tindie.com/stores/land_boards/]]
  
== Our Retro-Computer Hardware ==
+
== Grant Searle's FPGA MultiComp Project ==
  
=== MultiComp On EP2C5 ===
+
FPGA Recreations of 6502, 6809, Z80, and Z80 Vintage Computers
 
 
* [[EP2C5-DB|Land Boards EP2C5-DB FPGA Retro-Computer card]]
 
** Attaches to [[Cyclone_II_EP2C5_Mini_Dev_Board]]
 
** EP2C5 has 26 of 512x9 SRAM blocks
 
** Duplicates Grant's design down to the same pin maps
 
* 6 bit video on VGA (2:2:2 R:G:B)
 
* 128KB of SRAM for banked use in CP/M
 
* PS/2 Keyboard Mini-DIN connector
 
* Connector for serial ports
 
** Can attach inexpensive FTDI USB to serial converter
 
** Supports hardware handshake for high speed serial
 
* SD Card
 
* DC power jack (on FPGA card)
 
 
 
[[File:P1743-720PX.jpg]]
 
 
 
=== MultiComp On RETRO-EP4CE15 ===
 
 
 
* [[RETRO-EP4CE15|Land Boards RETRO-EP4CE15 design]]
 
** [https://www.aliexpress.com/item/32949281189.html EP4CE15 Cyclone IV FPGA Card] (tested)
 
** [https://www.aliexpress.com/item/4001310584093.html EP4CE55 Cyclone IV FPGA Card] (untested)
 
** [https://www.aliexpress.com/item/1000006622149.html 5CEFA2F23 Cyclone V FPGA Card] (tested)
 
** [https://www.aliexpress.com/item/1005001782703399.html 5CEFA5F23 Cyclone V FPGA Card] (untested)
 
** 1MB Fast SRAM
 
** FTDI FT230XS USB-to-Serial Interface with Hardware Handshake
 
** 6-bit (2:2:2) VGA
 
** PS/2 connector
 
** 5V Power Module
 
** 46 I/O connections on 50-pin header
 
 
 
[[File:RETROEP4CE15_REV4_EDGEVIEW-720PX.jpg]]
 
 
 
=== MultiComp On RETRO-EP4 ===
 
 
 
* [[RETRO-EP4|Land Boards RETRO-EP4 design]]
 
** Attaches to [[Cyclone_II_EP2C5_Mini_Dev_Board|Cyclone II EP2C5 Mini Dev Board]]
 
** 512K Fast SRAM
 
** FTDI USB-to-Serial Interface with Hardware Handshake
 
** 6-bit (2/2/2) VGA
 
** PS/2 connector
 
** 5V Power Module
 
** Lot of I/O connections
 
 
 
[[File:RETRO-EP4_TOP_BOTTOM-720px.jpg]]
 
 
 
=== MultiComp On BASE-EP4CE6 ===
 
 
 
* [[BASE-EP4CE6|Land Boards BASE-EP4CE6 card]] is a breakout board
 
** Attaches to [https://www.waveshare.com/wiki/CoreEP4CE6 CoreEP4CE6  FPGA Card]
 
** Can do up to 16K of Internal SRAM
 
 
 
[[File:BASE-EP4CE6-800pxV-197.jpg]]
 
 
 
== Purchased FPGA Cards ==
 
 
 
=== MultiComp On A4-CE6 Card ===
 
 
 
[[File:P1715-CROPPED-720PX.jpg]]
 
 
 
* [[A-C4E6_Cyclone_IV_FPGA_EP4CE6E22C8N_Development_Board|Cyclone IV FPGA EP4CE6E22C8N Development Board Wiki page]]
 
 
 
==== Features for MultiComp Use ====
 
 
 
* Enough Internal SRAM to make small (16KB) BASIC computers
 
* Includes VGA, PS/2 and CH340 USB-Serial converter
 
* A lot of I/O (26 pins) which can be easily accessed using [[EP4_FPGA_BREAKOUT|EP4 FPGA BREAKOUT]]
 
* LCD Display connector with additional I/O
 
 
 
==== Limitations on MultiComp compatibility ====
 
 
 
* No native SD Card storage but could be built using [[EP4_FPGA_BREAKOUT|EP4 FPGA BREAKOUT]] and [[SD_CARD_X49|SD CARD X49]]
 
* 1:1:1 video does not support 2:2:2 (bold characters under ANSI terminal)
 
* Serial Hardware handshake with a small rework to the card (2 wires)
 
 
 
==== Additional Features ====
 
 
 
* 8 Digit 7 Segment Display
 
* 8 position DIP switch
 
* 3 User pushbuttons, 1 DEV-OE pushbutton, 1 nCONFIG pushbutton
 
* 12 "Ring" LEDs - 2 removed and used for hardware handshake rework
 
* 24C04 I2C EEPROM
 
 
 
=== MultiComp On A4-CE10 Card ===
 
 
 
[[File:P1715-CROPPED-720PX.jpg]]
 
 
 
* Wiki page for [[A-C4E10_Cyclone_IV_FPGA_EP4CE10E22C8N_Development_Board|Cyclone IV FPGA EP4CE10E22C8N Development Board]]
 
 
 
==== Features for MultiComp Use ====
 
 
 
* Enough Internal SRAM to make small (32KB) BASIC computers
 
* Includes 5:6:5 VGA, PS/2 and CH340 USB-Serial converter
 
* A lot of I/O (26 pins) which can be easily accessed using [[EP4_FPGA_BREAKOUT|EP4 FPGA BREAKOUT]]
 
* LCD Display connector with additional I/O
 
 
 
==== Limitations on MultiComp compatibility ====
 
 
 
* No native SD Card storage but could be built using [[EP4_FPGA_BREAKOUT|EP4 FPGA BREAKOUT]] and [[SD_CARD_X49|SD CARD X49]]
 
* 1:1:1 video does not support 2:2:2 (bold characters under ANSI terminal)
 
* Serial Hardware handshake with a small rework to the card (2 wires)
 
 
 
==== Additional Features ====
 
 
 
* 8 Digit 7 Segment Display
 
* 8 position DIP switch
 
* 3 User pushbuttons, 1 DEV-OE pushbutton, 1 nCONFIG pushbutton
 
* 12 "Ring" LEDs - 2 removed and used for hardware handshake rework
 
* 24C04 I2C EEPROM
 
 
 
=== MultiComp On A_ESTF_V2_EP4CE22 Card ===
 
 
 
[[File:A-ESTF_001_720px.jpg]]
 
 
 
* [[A-ESTF_V2_EP4CE22_Board|A_ESTF_V2_EP4CE22 Card Wiki page]]
 
 
 
==== Features for MultiComp Use ====
 
 
 
* Includes VGA, PS/2 and USB-Serial converter
 
* A lot internal SRAM (up to 56KB)
 
* MicroSD card socket with card detect LED
 
 
 
==== Limitations on MultiComp compatibility ====
 
 
 
* No external SRAM but very large SDRAM
 
* A lot of I/O options
 
* Not widely available
 
* Has no USB-Serial Interface (has RS-232)
 
 
 
==== Additional Features ====
 
 
 
* A lot of I/O pins on the base board and on the FPGA board
 
* Eight 7 Segment Displays
 
* 3x3 matrix of pushbutton switches
 
* 3 user pushbutton switches on baseboard
 
* 3 user pushbutton switches on FPGA board
 
* Buzzer
 
* IR receiver
 
* Power switch
 
* 24C02 I2C EEPROM
 
* 8 position DIP Switch
 
 
 
=== MultiComp On ZrTech Cyclone IV FPGA Card ===
 
 
 
[[File:C4_Dev_687-720px.jpg]]
 
 
 
* [[Cyclone_IV_FPGA_EP4CE6E22C8N_Development_Board_USB_V2|EP4 FPGA card Wiki page]]
 
* Marked as zrTech V2.00
 
* We did a [https://www.youtube.com/playlist?list=PLn__0BqzWEWPk0-VW3kEpMNA81sIbhj6n YouTube video series on this card].
 
 
 
==== Features for MultiComp Use ====
 
 
 
* Includes VGA, PS/2 and USB-Serial converter
 
* Enough Internal SRAM to make small (16KB) BASIC computers
 
 
 
==== Limitations on MultiComp compatibility ====
 
 
 
* Very limited I/O
 
** Most of the I/O pins are shared with the 16-bit Video
 
** Would require removing R-packs to gain I/O
 
* Driver for USB-Serial doesn't work under Windows 10 (painful workaround)
 
* No SD Card storage
 
* No external SRAM but very large SDRAM (not supported yet in our builds)
 
* Would require a mod for serial hardware handshake (there's a pin or two free on the I/O which could at least do RTS)
 
 
 
==== Additional Features ====
 
 
 
* On/Off switch - nicer than plugging/unplugging DC power cable
 
* 4 pushbuttons
 
* Four digit 7 Segment Display
 
* IR LED
 
* Buzzer
 
* A/D with SMA connector
 
 
 
== Our FPGA Support Cards ==
 
 
 
These cards provide some of the missing functionality of the purchased FPGA card.
 
 
 
=== EP4 FPGA BREAKOUT ===
 
 
 
* [[EP4_FPGA_BREAKOUT|Wiki page for EP4 FPGA BREAKOUT]]
 
* Daughtercard for
 
** [[A-C4E6_Cyclone_IV_FPGA_EP4CE6E22C8N_Development_Board|Cyclone IV FPGA EP4CE6E22C8N Development Board]]
 
** [[A-C4E10_Cyclone_IV_FPGA_EP4CE10E22C8N_Development_Board|Cyclone IV FPGA EP4CE10E22C8N Development Board]]
 
 
 
[[File:EPXX-GVS-720px.JPG]]
 
 
 
=== VGAX49 ===
 
 
 
[[File:VGAX49_P901-cropped-720px.jpg]]
 
* [[VGAX49|VGAX49 Wiki page]]
 
* Digital VGA adapter
 
* 16-bit digital video
 
** 5:6:5 (R:G:B) mapping (maximum)
 
** 2:2:2 (R:G:B) mapping (option)
 
 
 
=== SD CARD X49 ===
 
 
 
[[File:SDCARDX49_P935_cropped-512px.jpg]]
 
 
 
* [[SD_CARD_X49|SD CARD X49 Wiki page]]
 
* SD or SDHC card adapter
 
* 5V to 3.3V regulator
 
* 3.3V to 5V TXS0104E level shifter
 
* Activity LED
 
 
 
=== TinyPS2 ===
 
 
 
[[File:TinyPS2_P899_cropped-720px.jpg]]
 
 
 
* [[TinyPS2|TinyPS2 Wiki page]]
 
* PS/2 keyboard or mouse to TTL Level Serial converter
 
* ATTiny85
 
* 115,200 baud
 
* 49x49mm ODAS form factor
 
* 4-40 mounting holes
 
 
 
=== FTDI-49MM ===
 
 
 
[[File:FTDI-P1746-CROPPED-720PX.jpg]]
 
 
 
* [[FTDI-49MM|FTDI-49MM Wiki page]]
 
* FTDI FT230X IC
 
* USB B connector (not micro or mini, but the beefy USB B connector)
 
* FTDI compatible pinout
 
* 3.3V or 5V selection jumper
 
* Header for 5V power distribution
 
* Rx and Tx LEDs
 
 
 
== Grant Searle's FPGA MultiComputer Project(s) ==
 
  
 +
* [[Multicomp_Hardware|Multicomp on Land Boards Cards]] - Hardware
 +
* [[Multicomp on Purchased Cards]]
 +
* [[FPGA Support Cards]]
 
* [https://github.com/douggilliland/MultiComp/wiki MultiComp Wiki Page on GitHub]
 
* [https://github.com/douggilliland/MultiComp/wiki MultiComp Wiki Page on GitHub]
 +
* [https://github.com/douggilliland/MultiComp Multicomp Github repo]
  
=== Multicomp Pages ===
+
=== Other Links ===
  
* [https://github.com/douggilliland/MultiComp Multicomp Github repo]
 
 
* [http://zx80.netai.net/grant/Multicomp/index.html Grant Searle's Multicomp page]
 
* [http://zx80.netai.net/grant/Multicomp/index.html Grant Searle's Multicomp page]
 
* [https://github.com/nealcrook/multicomp6809 Neal Crook's 6809 Multicomp Github]
 
* [https://github.com/nealcrook/multicomp6809 Neal Crook's 6809 Multicomp Github]
Line 248: Line 22:
 
=== Our MultiComp Retro-Computer Video Series ===
 
=== Our MultiComp Retro-Computer Video Series ===
  
==== EP2 Video Series ====
+
==== Cyclone II Video Series ====
 +
 
 +
<video type="youtube">7O0njivn-Po</video>
  
 
[https://www.youtube.com/playlist?list=PLn__0BqzWEWMcUgzBroNNJYQP1keD--gu Video Series]
 
[https://www.youtube.com/playlist?list=PLn__0BqzWEWMcUgzBroNNJYQP1keD--gu Video Series]
  
==== EP4 Video Series ====
+
==== Cyclone IV Video Series ====
  
 
[https://www.youtube.com/playlist?list=PLn__0BqzWEWPk0-VW3kEpMNA81sIbhj6n Video Series]
 
[https://www.youtube.com/playlist?list=PLn__0BqzWEWPk0-VW3kEpMNA81sIbhj6n Video Series]
Line 348: Line 124:
  
 
== Z80 CPU ==
 
== Z80 CPU ==
 +
 +
<video type="youtube">OdtYN3vPu_E</video>
  
 
* Land Boards [[Z80 in 3 Chips]]
 
* Land Boards [[Z80 in 3 Chips]]
Line 470: Line 248:
 
*BYE- Return to CP/M
 
*BYE- Return to CP/M
 
</pre>
 
</pre>
 +
* [https://altairclone.com/downloads/?fbclid=IwAR3BeIol8GOBKRSC6cB8lDMFSErRYjjmNtC4RQ3YpStdjeaSu-CLSTuLz5I Altair downloads]
  
 
=== Z80 Software Development ===
 
=== Z80 Software Development ===
Line 674: Line 453:
  
 
=== Our Build ===
 
=== Our Build ===
 +
 +
<video type="youtube">hHBiFK0d3Y4</video>
  
 
* [https://github.com/douggilliland/MultiComp/tree/master/MultiComp_On_RETRO-EP4CE15/MultiComp_6809_by_Neal_C-2019-04-08 Our FPGA Builds]
 
* [https://github.com/douggilliland/MultiComp/tree/master/MultiComp_On_RETRO-EP4CE15/MultiComp_6809_by_Neal_C-2019-04-08 Our FPGA Builds]
 +
* BASIC is a port of [https://handwiki.org/wiki/Color_BASIC Microsoft Extended BASIC] for the 6809-based Radio Shack Color Computer
  
 
=== Neal Crook's build ===
 
=== Neal Crook's build ===
Line 703: Line 485:
 
* [http://atjs.mbnet.fi/mc6809/index.html 6809 Emulation Page]
 
* [http://atjs.mbnet.fi/mc6809/index.html 6809 Emulation Page]
 
* [https://obsolescence.wixsite.com/obsolescence/the-6x0x-boards N8VEM 6809 Board]
 
* [https://obsolescence.wixsite.com/obsolescence/the-6x0x-boards N8VEM 6809 Board]
 +
* [https://www.6809.org.uk/asm6809/ asm6809 - Assembler]
  
 
== 68000 CPU ==
 
== 68000 CPU ==
Line 711: Line 494:
  
 
<video type="youtube">D9y7V0j5GsQ</video>
 
<video type="youtube">D9y7V0j5GsQ</video>
 +
 +
[[TG68 AMR Build]]
  
 
* Features
 
* Features

Revision as of 17:54, 14 August 2021

Tindie-mediums.png

Contents

Grant Searle's FPGA MultiComp Project

FPGA Recreations of 6502, 6809, Z80, and Z80 Vintage Computers

Other Links

Our MultiComp Retro-Computer Video Series

Cyclone II Video Series

Video Series

Cyclone IV Video Series

Video Series

6800 CPU

S120 Bus Computer

My first attempt to build a computer was around an MC6800 CPU so it has a soft spot in my heart, Back in 1977 (before my Ohio Scientific SuperBoard II I had my own homebrew computer. I never took any pictures of it and the hardware is long gone now. These are the pieces of it I remember.

  • Ran on Elco? 120 pin edge connector wire wrapped cards
  • 6800 Processor board running at 1 MHz
  • 2K of Static RAM board
  • 2716 EEPROM board (may have had 4 sockets total, don't recall for sure)
  • Front panel switches and LEDs to enter the address/data (Step/Insert) and blink lights

I remember getting it to run and I do remember blinking a light back and forth on it. Once I got the SuperBoard II, I stopped working on my own board.

It might be fun to reproduce that board!

Pieces to Reproduce my original S120 Bus Computer

  • Michael Holley's SWTPC 6800/6809 documentation collection
  • N8VEM RetroComputing Wikipedia page
  • Retrobrew Computers
  • Kim-1 board - Similar concept

Hardware

  • M6800 VHDL code from OpenCores

Software

  • AS68 Cross Assembler
  • ASM68C Cross Assembler
  • Collection of Assembly Language tools for the M6800
  • 6800 Basics
  • 6800 Assembly Language Programming (pdf) by Lance Leventhal
  • 6800 Instruction Set Cheat Sheet

M6800_MIKBUG - Tested/Works

This is an FPGA build of something similar to that machine

  • Fills a hole in Grant Searle's Multicomp (he hadn't finished a 6800 version)
  • MC6800 CPU
  • Running MIKBUG from back in the day (SmithBug ACIA version)
  • 12.5 MHz
  • 60K (external) RAM version
  • MC6850 ACIA UART
  • Video Display Unit (VDU)
  • PS/2 keyboard

Memory Map

  • $0000-$EFFF - 60KB external sRAM
    • $0000-$EEFF - User RAM area
    • $EF00-$EFFF - scratchpad used by MIKBUG
  • I/O Map
    • $FC18-$FC19 - VDU
    • $FC28-$FC29 - ACIA
        • Pin_60 of the FPGA swaps addresses of VDU and ACIA port
        • Installed (Pin_60 to Ground) uses Serial port
        • Removed uses VDU
  • $F000-$FFFF - MIKBUG ROM
    • I/O "hole" opened up at 0xFC00-0xFCFF

Systems

Software

Z80 CPU

Z80 P865-cropped-720px.jpg

Stackup (top to bottom)

Z80 PSOC P936-CROPPED-720PX.jpg

Z80-MBC2 Build

Z80-MBC2 Build Notes

CP/M on FPGA - by Grant Searle

CPM-2UARTs-NoVideo.PNG

  • Grant noted about the SD card interface:
... the SD controller is easy to control - in BASIC POKE the sector number, POKE the write command, 
POKE 512 bytes to the same location to write a sector, 
or POKE the sector number, POKE the read command, and PEEK 512 bytes to read a sector.

Retrobrew Multi-boot Multicomp Computer Builds

mc-2g-1024 Images

Retrobrew Computer Builds of the Multicomp Project(s)

CP/M Notes

  • CP/M is not case sensitive
  • REN NEWNAME.EXT=OLDNAME.EXT - Rename a file from the old to the new name
  • ERA FILE2ERA.EXT - Erase a file
  • Asterisk is wildcard
  • .COM are command files
  • PIP/PPIP - copy command (CP/M 2.2, CP/M 3)
    • CP/M 2.2 uses PIP
    • PIP NEWCOPY.EXT=COPYFROM.EXT - Copy from COPYFROM.EXT to NEWCOPY.EXT
    • CP/M 3 uses PPIP
  • Drive references A:
    • Drives go from A-???
  • LS is a better directory program

CP/M Resources on the Net

*BYE- Return to CP/M

Z80 Software Development

AZTEC C Compiler

  • Compile C code to CP/M executable
  • Aztec C Compiler Manual
    • C Vers. 1.06D 8080 (C) 1982 1983 1984 by Manx Software Systems
  • Example Code - HELLO2.C
int main()
{
  int i;
  for (i=0; i< 10; i++)
    printf("%d\n");
}
  • Compile code to assembly file
    • Creates a .ASM file
CC HELLO2.C
  • Assemble Code to object file
    • Creates a .O file
AS HELLO2.ASM
  • Link Code with C library to .COM executable file
LN HELLO2.O C.LIB

ALGOL-M Compiler

  • Fizzbuzz example
BEGIN

INTEGER FUNCTION DIVBY(N, D);
INTEGER N;
INTEGER D;
BEGIN
  DIVBY := 1 - (N - D * (N / D));
END;

INTEGER I;
FOR I := 1 STEP 1 UNTIL 100 DO
BEGIN
  IF DIVBY(I, 15) = 1 THEN
    WRITE("FizzBuzz")
  ELSE IF DIVBY(I, 5) = 1 THEN
    WRITE("Buzz")
  ELSE IF DIVBY(I, 3) = 1 THEN
    WRITE("Fizz")
  ELSE
    WRITE(I);
END;

END
  • To run compiler:
algolm fizzbuzz

  • Result is:
ALGOL-M COMPILER VERS 1.1
   0 ERROR(S) DETECTED
  • To run ALGOL interpreter
runalg fizzbuzz
  • Result is
ALGOL-M INTERPRETER-VERS 1.0


     1
     2
Fizz
     4
Buzz
Fizz
     7
     8

Microsoft BASIC Notes

  • SAVE "MYPROG.BAS"
  • LOAD "MYPROG.BAS"
  • SYSTEM -- Return to CP/M
  • NAME "OLDFILE.BAS" AS "NEWFILE.BAS"
  • NEW - Delete program
  • OUT 132,1 -- Output to I/O port 132
  • PRINT MEM - Free memory (6809 Extended BASIC)

Notes

NASCOM BASIC

  • OUT ADDR,DATA
  • INP(128) - Reads I/O address 128 (0x80)

6502 CPU

Ohio Scientific SuperBoard II - My first commercial personal computer

Osi-600.jpg

SuperBoard II

  • Manufacturer: Ohio Scientific
    • Model 600 Rev B Board Manual
  • Model: Superboard II ( Model 600 )
  • Available: 1978
  • Price: US $279 assembled
  • CPU: 6502
  • RAM: 4K static RAM, 8K max
  • CEGMON - Monitor in 4K of EPROM
  • Display: composite video, 30 X 30 text
  • Built-in keyboard
  • Single board design
    • I eventually got a RAM expansion card with Floppy Disk Controller
  • Ports: composite video, cassette
  • Storage: cassette
  • Microsoft BASIC
  • 2K Monitor ROM (CEGMON)
  • Compkit 101 - British clone of the SuperBoard II

Superboard II Documents

Keyboard Layout

Opkbd.jpg

CC65 - C Compiler for the 6502 and OSI C1P

SuperBoard II Emulator

BASIC Programs

10 I=1
20 PRINT "HELLO DAVEY"
30 I=I+1
40 IF I < 5 GOTO 20

SuperBoard II/ Retro-Tech Refresh

I was looking around for a way to recreate my OSI Superboard and found Grant Searle's design.

6809 CPU

Our Build

Neal Crook's build

Neal started from Grant Searle's Multicomp and fixed a number of issues with the VHDL code.

Other Docs

68000 CPU

Various 68000 builds

TG68_AMR Design

TG68 AMR Build

  • Features
    • 68000 Core
    • SDRAM support
    • VGA Framebuffer
      • Pixel dithering maps 24-bit video to six bits
      • Various resolutions
      • Stored in SDRAM
    • PS/2 Keyboard and Mouse support
    • SD Card support
  • Runs on RETRO-EP4CE15 basecard
    • VGA connector
      • 6 bit video (2:2:2)
    • PS/2 connector
    • FTDI USB to serial converter
      • Genuine FT230XS FTDI USC to Serial chip
      • USB B
      • Tx/Rx LEDs
    • SD or SDHC Card
      • Can do micro SDHC card using SD card adapter

TG68_AMR Links

TS2 design with Multicomp parts

TS2 Links

68000 Software

Other People's 68000 Builds

RISC V CPU

BASIC

DEC (Digital Equipment Corp) Computers

PDP-4

PDP-8

Build of Tom Almy's PDP-8 FPGA (Working 2021-May)

My build is based on Tom Almy's book The PDP-8 Class Project: Resoling An Old Machine.

OpenCores PDP-8 Build

Others PDP-8 FPGA

PDP-8 Documents and Programming

PiDP-8

PDP-10

PDP-11

My PDP-11 (pdp2011) FPGA builds

Other PDP-11 FPGA builds

PDP-11 Software

Terminal

Grant Searle Terminal Design

  • Uses two Arduino'ish processors to implement an entire terminal
    • NTSC output
    • PS/2 Keyboard input
  • Grant Searle's Monitor Keyboard Design

ATMega328Video 2.2.gif

  • Older AtMEGA32 version of Monitor Keyboard Design

SerialTerminal-P70002-cropped-720px.jpg

External Sites

PiGFX

  • PiGFX is a bare metal kernel for the Raspberry Pi that implements a basic ANSI terminal emulator with the additional support of some primitive graphics functions.
  • It can be driven by pushing characters to the raspi UART.

https://raw.githubusercontent.com/fbergama/pigfx/master/doc/scr1.jpg

RetroBrew Computers Site