Reverse engineering of the G305 mouse by Logitech
Spec | Range | Unit |
---|---|---|
DPI | 200 - 12000 | - |
Max acceleration | 40 | g |
Max Tracking speed | 400 | I/s |
Report Rate | 1 | kHz |
Processor Core | 32-bit ARM | - |
Claimed Battery Life | 250 | hours |
Characteristic | Range | Unit |
---|---|---|
Active Power | 10 | mW |
Idle Power * | 4 | mW |
Sleep Power ** | 200 | uW |
Deep Sleep Power *** | ? | |
Turn On Voltage **** | 1.35 | V |
Max Voltage ***** | 2.0 (3.6?) | V |
* No movement
** After approximately 90 seconds idle
*** After ~10 minutes of sleep? (to be measured)
**** Below this voltage the device is consistently unable to start
***** The device can tolerate more (tested up to 5.5V),
but above 4.8V it seems to consume unusually high power during Deep Sleep,
and above 2.0V the main voltage bus (nominal 2.0V) follows the input voltage (the same appens with the led 3.7V bus) meaning it goes over
the normal opperating conditions, still unkown if it has any long term impact (cryomods is currently running a long term test on one), suspission is that it is generally safe.
These are rough conservative approximations (though measured with fairly good equipment). Measurements on a single personal device.
Frequency range: 2.402-2.481 GHz Modulation Technology: GFSK
PCB as populated a Ceramic chip Antenna capable of 2.4 to 2.4835GHz.
FCC Documents for the mouse.
Battery | Weight [g] | Nominal Voltage [V] | Capacity [mAh] | Capacity [mWh] | Active Battery Life [h] |
---|---|---|---|---|---|
ALkaline LR6 (AA) | 1.5 | 1800 โ 2850 | 2700 - 4275 | 270 - 428 | |
ALkaline LR03 (AAA) | 1.5 | 860 โ 1200 | 1290 - 1800 | 129 - 180 | |
Lithium 14500 (AA) | 3.6 | 600 - 840 (1600 @ 1.5V) | 2160 - 3024 (2400 @ 1.5V) | 216 - 302 | |
Lithium 10440 (AAA) | 3.6 | 350 | 1260 | 126 | |
PR675 | 1.85 | 1.4 | 550 - 600 | 770 - 840 | 77 - 84 |
Super Capacitor 70F | 18 | 2.7 | - | - | 5.83 |
Super Capacitor 30F | 6.9 - 9.7 | 2.7 | - | - | 2.5 |
source: AAA Battery, source: AA Battery
Frequencies: 2.402 to 2.481GHz
Modulations technology: GFSK
Antenna Type: Printed
MCU: TI CC2544
Reverse engineering of the receiver is not planned
The hardware was traced in gimp, and can be analyzed in there too (everything is layered), file is here.
Whatch out, the top is mirrored!
CAD drawings of the G305 available in cad
credit to inornate on thingiverse.
The main board consists of:
- The HERO sensor
- A NRF52810 MCU in QFN-48
- unidentified boost converter 1
- unidentified boost converter 2
- 3x unidentified mosfet
- unidentified common anode RGB LED
- chip antenna
- 16MHz crystal?
The PCB contains the following testpoints:
testpoint | Funcion | Additional Info |
---|---|---|
TP1 | VIN + | Direct from battery 1.5V |
TP2 | VIN - | Direct from battery |
TP3 | Does not Exist? | |
TP4 | Does not Exist? | |
TP5 | Does not Exist? | |
TP6 | P0.04 | Unused Pin Breakout |
TP7 | Does not Exist? | |
TP8 | Does not Exist? | |
TP9 | Does not Exist? | |
TP10 | GND | |
TP11 | VDD | |
TP12 | SWDIO | |
TP13 | SWCLK | |
TP14 | RESET | |
TP15 | P0.22 | SWO? |
TP16 | P0.08 | Unused Pin Breakout |
TP17 | P0.09 | Unused Pin Breakout |
TP18 | P0.10 | Unused Pin Breakout |
TP19 | P0.29 | Unused Pin Breakout |
TP20 | P0.30 | Unused Pin Breakout |
TP21 | P0.31 | Unused Pin Breakout |
TP22 | P0.27 | Unused Pin Breakout |
TP23 | P0.28 | Unused Pin Breakout |
The MCU is a nRF52810 from nordicsemi, ARM Cortex M4 Package: QFN-48 Endianness of the MCU: Little Endian
Pin name | Function |
---|---|
P0.11 | CS |
P0.12 | MOSI |
P0.13 | MISO |
P0.14 | SCLK |
~ | ~ |
P0.15 | LMB |
P0.16 | RMB |
P0.17 | MMB |
P0.18 | forward side button |
P0.19 | back side button |
P0.20 | dpi button |
~ | ~ |
P0.23 | encoder pull up resistors (power saving) |
P0.00 | wheel encoder |
P0.01 | wheel encoder |
~ | ~ |
P0.02 | battery analog input |
P0.03 | 3.7V (RGB VDD) enable |
~ | ~ |
P0.05 | red LED |
P0.06 | green LED |
P0.07 | blue LED |
Initially plans were made to break APPPROTECT and dump the firmware, but it appears logitech never enabled it (you ok? lol)
The G305 comes with a HERO sensor, made in house by logitech, based on the mercury.
A reverse engineering effort towards this sensor will be made in a separate repo hero-re.