XE8000EV121 Semtech, XE8000EV121 Datasheet - Page 9

• Manufacturer Part Number: XE8000EV121
• Description: BOARD EVAL FOR SX8723/24
• Manufacturer: Semtech

Specifications of XE8000EV121

• Main Purpose: Interface, Sensor to ADC Interface, Programmable
• Embedded: No
• Utilized Ic / Part: SX8723, SX8724, SX8725
• Primary Attributes: Signal Conditioning for Bridge-Type Sensors
• Secondary Attributes: GUI, Up to 16-Bit, Programmable Gain of 1/12 ~ 1000, I2C Interface
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

ADVANCED COMMUNICATIONS & SENSING
3 Hardware description
3.1 XE8000EV121 Board features
3.2 Communication between PC, Gateway and SX8723/24/25
The communication protocol between the PC and the gateway is made of frame exchanges. A frame is
composed of a type, a size and a customized data buffer. There are 3 different types of frame: command
request frame, command response frame and data frame.
The command request frame is sent by the PC to the gateway. The command response frame is sent by the
gateway to the PC as a response to a command request. There is a command response sent for every
command request received.
The command request frame and command response frame are implied in the following procedure:
The data frame is used to send the measured value from the SX87xx ADC to the PC.
The data frame is implied in the following procedure:
V1.7 © 2008 Semtech Corp.
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1- PC sends a command request to the gateway via the UART.
2- The gateway will execute the command (using I2C connection with SX87xx).
3- The gateway will send a command response frame with the command result to the PC via the UART.
1- SX87xx validate its READY output.
2- The gateway fetches the ADC measured value (using I2C connection with SX87xx).
3- The gateway will send a data frame with the measured value to the PC via the UART.
Ease the access to every SX8723/24/25 pin.
Dedicated interfaces for connection to the external world.
USB interface for communication between the GUI and the chip.
Power supply flexibility (USB, battery, DC connector…).
User interface (LEDS, buttons…).
PC
Cmd req
Cmd resp
Data
Figure 6 Hardware block diagram
UART
USB
to
Cmd req
Cmd resp
Data
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SX8723/24/25 Evaluation Tools XE8000EV121
Gateway
Ready
I2C
SX87xx
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