DSPIC33FJ128GP706A-E/MR Microchip Technology, DSPIC33FJ128GP706A-E/MR Datasheet - Page 52

• Manufacturer Part Number: DSPIC33FJ128GP706A-E/MR
• Description: 16 Bit MCU/DSP 40MIPS 128KB FLASH 64 QFN 9x9x0.9mm TUBE
• Manufacturer: Microchip Technology
• Series: dsPIC™ 33Fr

Specifications of DSPIC33FJ128GP706A-E/MR

• Core Processor: dsPIC
• Core Size: 16-Bit
• Speed: 40 MIPs
• Connectivity: CAN, I²C, IrDA, LIN, SPI, UART/USART
• Peripherals: AC'97, Brown-out Detect/Reset, DMA, I²S, POR, PWM, WDT
• Number Of I /o: 53
• Program Memory Size: 128KB (128K x 8)
• Program Memory Type: FLASH
• Ram Size: 16K x 8
• Voltage - Supply (vcc/vdd): 3 V ~ 3.6 V
• Data Converters: A/D 18x10b/12b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 125°C
• Package / Case: 64-VFQFN, Exposed Pad
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Eeprom Size: -
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

MCP3909 / dsPIC33F 3-Phase Energy Meter Reference Design
6.2
6.3
DS51723A-page 52
TEST CONNECTION COMMAND
TOTAL DATA REQUEST
Variant-length frame structure is used and data communiate in bytes. The command
protocol structure is defined as following.
TABLE 6-2:
• The START word has 2 bytes, which are 0x00, 0xFF ( PC to target board) or 0xFF,
• Command word is 1 byte which indicates the type of the command
• Data length word is 1 byte that indicates the length of data field
• The data field word has multiple byte(s) that varies with command types
• Checksum word is a single byte, whose content equals to the XOR value of all
• Stop word is 1 byte with the content of 0xE0
This command is sent from the PC to the meter to setup and test the connection.
TABLE 6-3:
TABLE 6-4:
This is the main command retrieves all the calcuated data from the dsPIC33F. This
command gathers data from all 3 phases including total energy, power, and power
factor data.
TABLE 6-5:
TABLE 6-6:
0xFF, 0x00
0xFF, 0x00
0xFF, 0x00
0xFF, 0x00
0x00 (target board to PC)
bytes sent before it
2 Bytes
START
START
START
START
START
Command
Command
Command
Command
Command
1 Bytes
TYPICAL PROTOTOL
PC TO METER (7 BYTES)
METER RESPONSE (8 BYTES)
PC TO METER (7 BYTES)
METER RESPONSE (104 BYTES)
0x41
0x42
0x42
0x43
Length
Length
Length
Length
Length
1 Byte
Data
Data
0x00
Data
0x02
Data
0x00
Data
0x62
0xA5, 0X5A
Data Field
Data Field
Data Field
Data Field
Data Field
98 bytes
N Bytes
0x00
0x00
Check Sum
Check Sum
Check Sum
Check Sum
Check Sum
© 2009 Microchip Technology Inc.
1 Byte
XX
XX
XX
XX
1 Byte
STOP
STOP
STOP
STOP
STOP
0xE0
0xE0
0xE0
0xE0