G. Laroche Web site |
µP
AVR ATMega8 board for PLL MC145170 management
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Summary
This board allow to manage a FM transmitter
including a Phase Locked Loop (PLL)on a serial bus (SPI) like a MC145170.
A curent frequency is memorised in EEPROM to configure PLL at power up.
Three auxiliairy frequencies are available for maintenance fonction and/or
HF adjust.
A local interface include 4 keys and a LCD display enable to modify transmitter parameters.
This board can be completely drived from a serial link RS232 (19200 Bds,8b data,2b stop, no parity).
A temperature sensor enable to control working temperature and 2 analog input are used for HF power measure (Forward and Reflected).
Information about TOS protection activation is processed by this board to inform user (local and remote) on a TOS Alarm.
Click on reactive zone of following picture for more information(connectors, adjust,...)
Diagram and board are available in a zip file for Eagle 4.16 :
Diagram
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Board
(top view) |
Board |
PFM8 board file for Eagle 4.16 : PFM8_eagle.zip |
V1.0 software usage
Local interface include a 1 raw LCD display and 4 keys using for the following functions :
STORE | Store current frequency |
UP | Increase current frequency by 50KHz step |
DOWN | Decrease current frequency by 50KHz step |
QUICK | Quick change, select next auxiliary frequency among preset frequencies |
LCD display frequecy setting on PLL (main frequency or auxiliary frequencies)
The board can be controled by an RS232 link with the following features :
Baud rate | 19200 Bds |
Data size | 8bits |
Stop bits | 2 stop bits |
Parity | no parity |
Protocol | no protocol |
An help menu displaying available commands can be obtain by the command : '?'
Syntax commands is defined by the following format :
"command separating_space parameter"
Thecommands are associated to a single ASCII Character (example 'M' (or 'm') for Memorise curent frequency )
At least one space is necessary to split the the command from parameter(s)
Frequnecies for parameters are in 10KHz example : '9800' for 98.00 MHz (98 000 KHz)
Screen capture showing initialisation message followed by '?' and 'D' commands.
Software Version TI_PFM V1.0
V1.0 TI_PFM software version is an operational version based on a test and integration version (Test and Integration PFM).
So this version is limited to a basic function : to manage PLL with a curent frequency.
Some fonctionalities are not implemented in this first version :
RS232 receiving is managed with an intterrupt and a 16 bytes buffer.
Timer 1 is used to refresh initialisation message, in this vrsion it is not used later
C langage is used for this software, athough it's not an object langage, object approach was used for design.
Binary code is available by clicking on the following link:
Binary code and sources files are available under GNU General Public License (GPL) :
binary file ".hex"
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sources files
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Software:
V1.0 software version is operational, but don't use all functionnalities of board (see Functionnalities implementations)
A fully version software using all board's possibilities is actually in study and will be soon available on this site.
Hardware:
No board problem knows for this version 1.0, however, some features will be optimised for the next version :