Barkley

Barkley is the codename of the PS Vita Motion Sensor. It is also referred as "Motion" in the System Software SDK.

The Barkley name most likely refers to the microcontroller, but could also designate the whole sensing subsystem.

Hardware

The motion sensing subsystem is made of four components:

microcontroller
- communicates with Kermit via ?SPI?
- manages and samples the sensors
accelerometer
gyroscope
compass

There are two ICs near the microcontroller with the following markings:

 PR4100
  2029
 KGMBF

?Gyroscope? from unknown manufacturer

   0C9
   Y31
<QR-Code>

?Compass? from unknown manufacturer

Note: Both unknown ICs use a font on the package that looks like the STMicroelectronics font

Microcontroller: STMicroelectronics 'STM32P10SoE'
- Undocumented variant of the STM32F100
  - Features to be documented
Accelerometer: Kionix KXTC9
- Outputs analog data sampled by Barkley
Gyroscope: ?
Compass: Asahi KASEI AK8975C
- Connected to Barkley via I²C (7-bit slave address: 0x0C)

An IC with the following markings is found next to the KXTC9 and could be the gyroscope:

 3GA51H
  2141
 QT1AU

It has the same form factor and footprint as the PR4100 from DEM-3000H.

The STM32P10SoE ballout appears to be identical to the STM32F100xx value line:

STM32P10SoE ball mapping
Ball	Type	Description
A1	-	N/C
A2	-	N/C
A3	-	N/C
A4	-	N/C
A5	-	N/C
A6	-	N/C
A7	-	N/C
A8	-	N/C
B1	-	N/C
B2	PWR	VBAT
B3	I	AK8975 DRDY interrupt
B4	I	BOOT0 (tied to GND?)
B5	?	Kermit E25
B6	-	N/C
B7	?	GND via a capacitor near Ernie shield?
B8	-	N/C
C1	I	OSC_IN - Oscillator Input
C2	PWR	VSS_4
C3	I/O	AK8975 I²C data
C4	-	N/C
C5	-	N/C
C6	?	GND near Ernie via capacitor?
C7	?	GND near Ernie via capactior?
C8	-	N/C
D1	O	OSC_OUT - Oscillator Output
D2	PWR	VDD_4
D3	O	AK8975 I²C clock
D4	PWR	VSS_3
D5	PWR	VSS_2
D6	PWR	VSS_1
D7	-	N/C
D8	?	3GA51H pin 25
E1	I	nRST (Ernie J4)
E2	-	N/C
E3	?	?
E4	PWR	VDD_3
E5	PWR	VDD_2
E6	PWR	VDD_1
E7	-	N/C
E8	-	3GA51H pin 23
F1	PWR	VSSA (Analog domain)
F2	I	KXTC9 pin 6 (X-axis)
F3	?	?
F4	?	?
F5	?	3GA51H pin 7
F6	?	Kermit A26
F7	I	Kermit SPI1 MOSI (Kermit Z12)
F8	O	Kermit SPI1 MISO (Kermit AA13)
G1	PWR	VREF+ (ADC reference voltage)
G2	?	?
G3	-	N/C
G4	I	KXTC9 pin 8 (Z-axis)
G5	?	3GA51H pin 1
G6	I	PB2/BOOT1 - tied to GND
G7	-	N/C
G8	I	Kermit SPI1 clock (Kermit Z13)
H1	PWR	VDDA (Analog domain)
H2	?	Connected to a 3-pin IC near GC slot
H3	?	GND via a capacitor near Ernie shield?
H4	?	3GA51H pin 5
H5	I	KXTC9 pin 7 (Y-axis)
H6	?	3GA51 pin 3
H7	-	N/C
H8	I	Kermit SPI1 chip select (Kermit AA12)

The 3GA51H IC is linked only to the STM32P10SoE - all other pins are used for power or left unconnected.