MCP2140DM-TMPSNS Microchip Technology, MCP2140DM-TMPSNS Datasheet - Page 14

• Manufacturer Part Number: MCP2140DM-TMPSNS
• Description: BOARD DEMO FOR MCP2140
• Manufacturer: Microchip Technology

Specifications of MCP2140DM-TMPSNS

• Main Purpose: Interface, IrDA
• Embedded: Yes, MCU, 8-Bit
• Utilized Ic / Part: MCP2140
• Primary Attributes: IrDA Controller with PIC18F MCU and Temp Sensor Temp
• Secondary Attributes: Set up as a Data Logger
• Processor To Be Evaluated: MCP2140
• Interface Type: ICSP
• Silicon Manufacturer: Microchip
• Silicon Core Number: MCP2140
• Kit Application Type: Sensing - Temperature
• Application Sub Type: Temperature Sensor
• Kit Contents: Board
• Rohs Compliant: Yes
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant, Lead free / RoHS Compliant
• Other names: MCP2140DM-TMPSNSR; MCP2140DM-TMPSNSR

MCP2140 IrDA
DS51487A-page 10
2.3.2
There are two programs that can be demonstrated on the demo board. These are:
• The transmission of a 250 byte data string from a table in the PIC18F1320 to the
• The transmission of the “temperature” reading of the TC1047A to the Primary
Typical Primary devices include Palm or Pocket PC PDAs and Laptop PCs with an IrDA
standard infrared port.
The PIC18F1320 source code for the MCP2140 IrDA Standard Wireless Temperature
Sensor Demo Board is available for download from the Microchip web site at
www.microchip.com.
2.3.2.1
This program will be selected when the RESET switch is depressed and then released
(with the S2 switch not pressed). The PIC18F1320 will initialize the system and wait to
receive a data byte. Once a data byte is received, the PIC18F1320 will transmit a
250-byte table from memory to the MCP2140.
The PIC18F1320 follows the flow control of the MCP2140 to ensure that data is not lost.
The MCP2140 handles all the IrCOMM protocol for the data packets that it receives
from the PIC18F1320.
Once the table has completed transmission, the PIC18F1320 will wait to receive the
next character that will cause the 250-byte table to be transmitted (again).
The 250-byte data table transmitted from the MCP2140 IrDA Standard Wireless Temper-
ature Sensor Demo Board to the Primary device is shown in Appendix D. “MCP2140
250 Byte Data Transmit Table”. These values will be displayed in the Primary device’s
Terminal Emulation program window.
2.3.2.2
This program will be selected when both the RESET and S2 switches are depressed,
the RESET switch is released and the S2 switch is held momentarily. The PIC18F1320
will initialize the system and wait to receive a data byte. Once a data byte is received,
the PIC18F1320 will continuously transmit the following string:
The PIC18F1320 follows the flow control of the MCP2140 to ensure that data is not lost.
The “measured” temperature will vary as a result of the system voltage of the demo
board. This is due to the PIC18F1320 being powered directly from the AAA batteries
and the A/D module using V
The current firmware implementation will transmit a larger value to the Primary device
as the battery voltage decreases, given a constant temperature.
A firmware technique to correct for this would be to use the PIC18F1320 LVD module.
A hardware technique would be to use a voltage regulator to ensure that the system
voltage remains constant, regardless of the voltage output of the batteries.
®
Primary device.
device.
Standard Wireless Temp Sensor Demo Board
“Temp = xx” to the MCP2140, approximately once per second, where xx is the
temperature in °C.
The Embedded System Firmware
“TRANSMIT 250 BYTE DATA STRING” PROGRAM DESCRIPTION
“TRANSMIT TEMPERATURE” PROGRAM DESCRIPTION
DD
as its reference voltage.
 2004 Microchip Technology Inc.