MCP3909EV-MCU16 Microchip Technology, MCP3909EV-MCU16 Datasheet - Page 18

• Manufacturer Part Number: MCP3909EV-MCU16
• Description: EVALUATION BOARD FOR MCP3909
• Manufacturer: Microchip Technology

Specifications of MCP3909EV-MCU16

• Number Of Adc's: 2
• Number Of Bits: 16
• Sampling Rate (per Second): 15k
• Data Interface: Serial
• Inputs Per Adc: 1 Differential
• Input Range: ±1 V
• Voltage Supply Source: Analog and Digital
• Operating Temperature: -40°C ~ 85°C
• Utilized Ic / Part: MCP3909
• Silicon Manufacturer: Microchip
• Application Sub Type: ADC
• Kit Application Type: Data Converter
• Silicon Core Number: MCP3909
• Kit Contents: Board
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

MCP3909 ADC Evaluation Board for 16-Bit MCUs User’s Guide
DS51777A-page 14
The CCSPI global value is the counter that indicates if the SPI happens soon after the
INT3, and the value present in the SPI is CH0, or if a previous SPI interrupt happened
and now is time to save value of CH1. After saving the samples into MCU, a small pulse
is sent on CS, to the MCP3909, to prepare it for a new conversion. The acquired data
is saved in form of two vectors in SRAM, one for CH0 and ne for CH1.
Finally, the Timer 5 interrupt and UART TX interrupt are enabled. The first Character
sent to UARt is:!.
FIGURE 2-2:
Set SPI on 16 bit Mode;
External Interrupt 3
Increment ccspi;
Disable INT3;
Enable SPI;
Read CH0;
Save word;
ccspi=0?
YES
ADC Communication Flowchart.
NO
Increment ccspi;
Save word;
Read CH1;
ccspi=1?
YES
© 2008 Microchip Technology Inc.
Disable SPI interrupt;
Save data in buffer
NO
Enable UART TX
Enable INT3;
Sent char 0d33;
Enable timer 5
Buffer Full?
ccspi=0;
interrupt;
interrupt;
ccspi=2;
YES
YES