This section describe the ArduCAM shield Rev.C hardware feature and user guide. For information about Rev.B, please refer here.


ArduCAM shield hardware integrates all the necessary components to interface with camera modules. User only need a extra support camera modules and a TF/SD card to start image capture.

The shield provide the following features:

  • Dedicate DigtalVideoPort Camera Module Interface
  • Standard SPI slave bus interface
  • 3.2” TFT Color LCD Screen(a)
  • Build-in 3Mbit FIFO Memory
  • TF/SD Card Reader with LED indicator
  • Use Arduino SPI / I2C dedicate pin out
  • Well mated with UNO/MEGA2560/DUE/Leonardo boards

Note: (a) Model ArduCAM-F doesn’t not include a 3.2” LCD screen

ArduCAM Shield Pin Out

ArduCAM shield includes to sets of pin out see Figure 1,  they are identical in function. One is Arduino standard, it can be well mate with standard Arduino boards like UNO, MEGA2560, Leonardo and DUE etc. The other one is alternative port which can be connect to any platform like Raspberry Pi. The detail pin out for each see Table 1 and Table 2.

Figure 1 ArduCAM pin out


Table 1 Arduino Standard Pin Out

Index Arduino Pins Description
1 I2C_SCL I2C clock
2 I2C_SDA I2C data
3 SPI_SCLK SPI clock
4 SPI_MISO SPI Master In Slave Out
5 SPI_MOSI SPI Master Out Slave In
6 9 SD/TF Card Chipselect
7 10 ArduCAM Shield Chipselect
8 Reset Arduino Reset Input
9 5V 5V Power Input
10 GND Gound

Table 2 Alternative Pin Out

Index Arduino Pins Description
1 I2C_SDA I2C data
2 I2C_SCL I2C clock
3 CS_n ArduCAM Shield Chipselect
4 SD_CSn SD/TF Card Chipselect
5 SPI_MISO SPI Master In Slave Out
6 SPI_MOSI SPI Master Out Slave In
7 SPI_SCLK SPI clock
8 Trigger Snapshot Input
9 RST Reset Input
10 GND Gound
11 5V 5V Power Input

Camera Interface

CMOS image sensor interface divided into two catalogs, one is DVP (Digital Video Port) interface, the other is MIPI Mobile Industry Processor Interface. The main difference between DVP and MIPI is that DVP is parallel interface and the MIPI interface is high speed differential serial interface. MIPI interface provide higher data band width than DVP interface and support higher resolution and frame rate. Because the complexity and need additional hardware of MIPI interface, we only discuss DVP interface here.

For a standard DVP image sensor you will find the following signals:

  • SCL: I2C compatible clock signal for sensor registers configuration
  • SDA: I2C compatible data signal for sensor registers configuration
  • XCLK: clock input to the sensor
  • PCLK: clock output from the sensor,
  • HREF: Line valid signal
  • VSYNC: Frame valid signal
  • Data[N-1..0]: Data output from the sensor, N is the internal ADC bit width.

ArduCAM shield provide a DVP interface which support wide range of camera modules from 0.3MP to 5MP. The camera modules should line up with the shield based on Pin1 shown in the Figure 2 and Table 3 provide camera interface pin out on the shield.

Figure 2

CAM Pin Out

CAM Pin Out

Table 3 Camera Interface Pin Out

Pin Signal Pin Signal
1 +3.3V 2 GND
9 D7 10 D6
11 D5 12 D4
13 D3 14 D2
15 D1 16 D0


The ArduCAM shield includes a ArduChip which handle complex timing between MCU and LCD, Camera, FIFO. It exports a standard SPI serial interface shown in Table 4 and can be interfaced with wide range of micro-controller. MCU control the shield through a set of ArduChip internal registers shown in Table 6.

Table 4 ArduCAM shield SPI Interface

Signal Arduino UNO Pin Description
SCL I2C_SCL I2C clock
SDA I2C_SDA I2C data
MISO SPI_MISO SPI master in slave out
MOSI SPI_MOSI SPI master out slave in
CSn 10 ArduCAM shield chipselect, active LOW
SD_CSn 9 TF/SD card chipselect,      active LOW

Bus Timing and Protocol

ArduCAM shield Rev.C use standard SPI slave bus protocol (CPOL = 0, CPHA = 0). One bus transaction composed by two 8bit access. Every bus transaction start with CSn goes low. The first 8bit is command phase, and the second 8bit is data phase. The bus timing shown in Figure 3 and Figure 4.

Figure 3 Bus Write Timing


Figure 3 Bus Read Timing


Data protocol in the command phase see Table 5

Table 5 Command Byte Protocol

Command Byte Protocol

Bits Bit[7] Bit[6] Bit[5:1] Bit[0]
ArduChip Internal Register 1: Write0: Read 0: R/W Register1: RO Register Register Address  bit[5:1] Register Address bit[0]
LCD Command Write 1 0 11111 1
LCD Data Write 1 0 11111 0
FIFO Read 0 0 11110 1

Table 6 ArduChip Registers

Address Name Mode Description
0x00 ARDUCHIP_TEST1 R/W Testing Register, only used in bus testing
0x01 ARDUCHIP_TEST2 R/W Testing Register, only used in bus testing
0x02 ARDUCHIP_MODE R/W Bus Mode selection .Bit[7:3]: Reserved Bit[2]: LCD to MCU, Bit[1]: Camera to LCD , Bit[0]: MCU to LCD
0x03 ARDUCHIP_TIM R/W Timing Control register. Bit[7..6]: Reserved. Bit[5]: FIFO power down, 1 = power down, 0 = normal operation. Bit[4]: reserved. Bit[3]: Camera data delay control. 1 = delay 1 clock, 0 = no delay. Bit[2]: LCD backlight control, 1 = backlight off, 0 = ON. Bit[1]: Camera VSYNC polarity control, 1 = Inverted, 0 = Normal. Bit[0]: Camera HREF polarity control, 1 = Inverted, 0 = Normal.
0x04 ARDUCHIP_FIFO R/W FIFO control Bit[1]: Write 1 to start a capture, Bit[0]: Reset the FIFO read and write pointer to ZERO.
0x40 ARDUCHIP_REV RO Bit[7:6]: Revision integer part. Bit[5:0]: Revision decimal part. Default value is 0xC0.
0x41 ARDUCHIP_TRIG RO Trigger input Register. Bit[7:4]: Reserved. Bit[3]: Capture complete flag, 1 = Complete, 0 = Busy. Bit[2]: Reserved. Bit[1]: Capture button status, 0 = pressed, 1 = released. Bit[0]: Frame start signal, equal to VSYNC

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