OSCR:HW5

Hardware version 5 of the OSCR modifies and improves on prior versions in many ways:

• Removed the battery module.
• Moved voltage toggling to the main PCB.
• Moved the GBx slot to the main PCB.
• Added a six-slot top PCB (previously "adapter PCB") which supports multiple systems at once without the need to swap top PCBs.

Additionally, revisions have added the following features:

• Automatic Voltage Selection (Vselect): Allows the firmware to control the voltage, replacing the mechanical switch and removing the need for the user to remember to manually set the voltage.
• Real-Time Clock (RTC): Keeps track of the date and time so that the timestamps of files on the SD card can be accurate.

Revision History

Hardware 5: Main PCB

Revision	Changes
1	Initial
2	Moved power and voltage switches to the right side of the main PCB.
3	Added test pads.
4	Added Vselect to the main PCB. Added/changed the OSCR logo (OSHW version).
5	Added RTC to the main PCB. Removed the LCD solder jumper and test pads. Improved the silkscreen/legend.
6	(Never pushed to the repository, contained errors.)
7	(Never pushed to the repository, contained errors.)
8	(Next revision, currently awaiting validation/testing.) Added a port compatible with USB Type-C® Power Delivery devices. * Robust protection on VBUS: * Protection against ±1 kV, 42 Ω IEC 61000-4-5 surge test for industrial signal lines * Maximum clamping voltage of 28.4 V at 40 A of 8/20 µs surge current * Survives over 5,000 repetitive strikes of 35 A 8/20 µs surge current at 125°C * Level 4 IEC 61000-4-2 ESD protection * IEC 61000-4-5 (8/20 µs): 40 A * IEC 61643-321 (10/1000 µs): 5 A * Ferrite bead for filtering out high-frequency noise. * IEC 61000-4-2 ESD protection for the CC1, CC2, and data pins. * CC1 and CC2 short-to-VBUS protection. * Negotiates up to 5V/3A from USB Type-C® Power Delivery-capable power supplies. * USB communication via CH340N. * Can be used with the ATmega2560 on the board or via the module. When using the module, do not connect cables to both USB ports at the same time. Added a 3.3V voltage regulator and related components. This allows for easier headless variants and the use of LCD modules which don't have a 3.3V output option. Added LEDs for each power rail (VBUS, 5V, 3V3, and VCC/CBUS). Added an option to install the clock generator components directly onto the PCB instead of the Adafruit-style clock generator module. Added an option to install the ATmega2560 and its related components directly onto the main PCB instead of the MEGA PRO MINI (Embed) module. Installing the ATmega2560 directly onto the main PCB enables additional options. * Gained access to 16 previously unavailable digital IO pins. 8 are used by new features, 2 are broken out to the cartridge adapter, and the remaining 6 are available for use. * Ability to control if power is provided to an attached cartridge via the firmware. When not used, the power LED labeled as CBUS is for VCC. * Added an RGB LED for showing status and error codes. * Added voltage monitors to 3V3, 5V, and VCC enabling the firmware to help detect issues with power and perform a sanity check on VCC before toggling CBUS on. Added an AUX connector to the bottom of the PCB which breaks out all of the power rails, the I2C pins, and the additional 16 pins gained by installing the ATmega2560 directly onto the PCB. This connector is intended to allow for future expansion without the need for a user to have to replace their main PCB or solder anything. The connector could also be used to implement the 16 additional IO pins via an IO expander. Top-PCB FPC headers added for connecting to supported top PCBs. New OSCR logo.

HW5 is also supported by the browser-based OSCR Firmware Updater located at OSCR.tools.