Microchip Technology Photodiode PGAPICtail, Руководство пользователя

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Overview

2004 Microchip Technology Inc. DS51514A-page 9
1.4.1 PC Platform
The Personal Computer (PC) shown in Figure 1-2 needs to run on Windows
®
98 SE or
later. It provides a convenient interface for the user, communicates with the other
boards and provides power through the USB connection.
1.4.2 PICkit™ 1 Signal Analysis PC Program
The PICkit™ 1 Signal Analysis PC Program configures and programs the PIC16F684
PICmicro
®
microcontroller on the Signal Analysis PICtail Daughter Board through the
USB port on the PICkit 1 Flash Starter Kit. It also imports data through the same
connection and displays the data in strip chart, histogram, FFT plot and oscilloscope
plot formats. Data can be output in CSV format for importing into a spreadsheet
program.
1.4.3 PICkit 1 Flash Starter Kit
The PICkit 1 Flash Starter Kit (DV164101) programs PICmicro
®
microcontrollers, using
the PIC16C745’s USB port to communicate with the PICkit 1 Signal Analysis PC
Program. It connects to the Signal Analysis PICtail Daughter Board via a header (see
Figure 2-1).
This board provides a 5V supply voltage for the daughter boards. It can drive
up to 5 µF on the supply; a larger capacitance may interfere with program timing.
1.4.4 PICkit 1 Firmware
This software resides on the PICkit 1 Flash Starter Kit’s PIC16C745 microcontroller.
Use version 2.0.2 or later.
1.4.5 Signal Analysis PICtail Daughter Board
This board is Microchip Development Tool AC164120. It connects to the PICkit 1 Flash
Starter Kit, which it uses for power and a communications link to the PC. The on-board
PIC16F684 has a 10-bit ADC that converts the Photodiode PGA PICtail™ Daughter
Board’s output voltage. The results are temporarily stored on the board’s 25LC640
serial EEPROM chips.
The +5V single supply voltage from the PICkit 1 Flash Starter Kit board is bypassed
with a bulk 1 µF capacitor and local 0.1 µF capacitors for each IC.
1.4.6 Firmware for the Signal Analysis PICtail Daughter Board
PICA2Dlab.hex
is the standard file that supports the PICkit™ 1 Signal Analysis PC
Program. The PGA and 10-bit ADC configuration are selected in the Signal Analysis
PC Program and written to the PIC16F684. The PIC16F684 then sends the
command(s) over the SPI bus to the PGA.
1.4.7 Interface Details
A more detailed look at how the Photodiode PGA PICtail™ Daughter Board interfaces
with the other boards is shown in Figure 1-3.