GCM-V5.1

GCM V5.1 :

• DOCUMENTS

  • Flipped ordering of version in CHANGELOG file
  • Updated the BOM and fix wrong J9 ref #5 #3
  • Small revision on the block diagram

• SCHEMATICS

  • Set version to 5.1
  • Fix conflict between U40 and U12, the BWRITE1 bus have been replaced by BWRITE2 on U12 #14
  • Removed the delay on ADDSCR_CLK #9
  • Fix a symbol issue where pins was flipped and not ordered causing a clock problem #7

• PCB

  • Set version to 5.1

  • Cleaning

  • All capacitor is now in 0805 size

  • For U22, U23, U24, the decoupling capacitor have been repositioned #13

  • J9 is now repositioned next to J12 with a step of 2.54mm #12

  • Back a little the MM1 connectors #8

  • Footprint of J7 have been correctly replaced #6

  • J12 have been correctly replaced with a male connector #4

  • Removed all decoupling capactior for the not used 12V power #11

  • More power decoupling next to the nano-fit power connector #10

GCM-V5.0

GCM V5.0 :

• GLOBAL

  • Switching "CERN-OHL v1.2" license to "CERN-OHLw v2 or later"
  • Renaming "librairies" folder to "libraries"

• DOCUMENTS

  • Adding the GCM datasheet
  • Adding the CHANGELOG file
  • Adding waveforms
  • Cleaning

• SCHEMATICS

  • Set version to 5.0
  • Replacing old custom "74CBTLV16212" symbol with the Kicad symbol "74CBTLV16212"
  • Replacing old custom "LTC6994-1" symbol with the Kicad symbol "LTC6994xS6-1"
  • Replacing old custom "LM810" symbol with the Kicad symbol "LM810"
  • Replacing all hidden power pins symbols (hidden pins bug)
  • Renaming "Main connector" to "SPS1 Processor connector"
  • Removing old symbols, cleaning
  • Replacing symbol "CD74AC238" with a new one
  • Replacing all used 74x1Gxx symbols
    (shared power pin fix, and visual)

• PCB

  • Removing/Cleaning old footprints
  • Set version to 5.0
  • Fixing 3D
  • Adding QRCode with the Github link

• SCHEMATICS FEATURES

  • Complete change of the clock generation
    Adding the "ECS-2200BX-500" crystal oscillator
    You will now be able to select : 50MHz
    or pre-division : /2, /4, /8, /16, /32, /64, /128, /256, /512, /1024, /2048, /4096, /8192, /16384, /32768, /65536
    Removing "~GLOBAL_CLK"
    More simple frequency control (switch to parallel control)
    Removing "LTC6903" (SPI frequency chip)
    Fixing unstable frequency change
    After a frequency change, the system now send a "SOURCE_RESET" pulse

    • Replacing "SN74LV163A" with "CD74AC161"
      Async reset
    • Put a Tpd delay to "ADDSRC_CLK"
    • "ADDSRC_CLK" is now directly connected to the CLK input of the 24bits counter

  • Renaming "ClockGenerator.sch" sheet to "fileClockGenerator.sch"

  • Renaming "Connector.sch" sheet to "fileConnector.sch"

  • Renaming "Peripherals.sch" sheet to "filePeripherals.sch"

  • Renaming "MemoryController.sch" sheet to "fileMemoryController.sch"

  • Renaming "MemorySlot1.sch.sch" sheet to "fileMemorySlot1.sch"

  • Renaming "MemorySlot2.sch" sheet to "fileMemorySlot2.sch"

  • Renaming "AddressCounter.sch" sheet to "fileAddressCounter.sch"

  • Renaming "AddressExchanger.sch" sheet to "fileAddressExchanger.sch"

  • Adding a seperate clock signal only for peripheral (PClockGenerator)

  • Applying PP1 standard for peripheral https://github.com/JonathSpirit/GComputer_standard

  • Applying MM1 standard for memory https://github.com/JonathSpirit/GComputer_standard

  • Mounting holes is now on schematics

  • Renaming "MAIN_RESET" to "POWER_RESET"

  • Renaming "SOURCE_RESET" to "LIGHT_RESET"

  • Renaming "RESET_CLK" to "GLOBAL_RESET"

  • MemoryController rework
    User can now control CE,WE,OE pins of the not selected memory source
    Applying MM1 standard, (3.3V)
    Renaming/Cleaning

GCM-V4.0

GCM V4.0 :
- Intial release