MCCNFG/DOS

Introduction

MCCNFG/DOS is a DOS application that will program the MC145170 chip in the EXP-1. 

In these days of Windows why write a DOS application?  Mainly because I had an elderly Compaq Contura 386 Notebook in my closet that I new would be usefull for something..... and acting as a programmer for the PLL turned out to be the something. 

MCCNFG/DOS gives you full control over the C, R and N registers of the PLL so it should be usable will all MC145170 installations with a little experimentation... particularly in the C values.  I suggest you obtain the Motorola MC145170 data sheet for a full description of the options that appear on the MCCNFG/DOS configuration page.

 

Installing MCCNFG

MCCNFG/DOS accesses the LPT1 port on your PC to program the PLL.  The port address is obtained automatically from the PC BIOS.  Becauses MCCNFG/DOS accesses the ports directly it will not run under Windows NT but should operate in a DOS Windows of Windows 3.x, Windows 95 or Windows 98. 

MCCNFG/DOS has been tested on machine ranging from a with processor speeds ranging from an 80386-20 to Pentium II-366 and in all cases successfully programmed the PLL.

MCCNFG/DOS is supplied as a ZIP file.  To install do the following:

Configuring MCCNFG/DOS for your PLL

When MCCNFG/DOS is started you will see a screen similar to:

Press F2 to open the configuration form.  You will see a screen similar to:

Configuration options with the recommended values for the EXP-1 are as follows:

Option EXP-1 Register Note
Phase Detector Output Polarity 0 C Not Inverted
Phase Detector A/B Selection 1 C Phase Detector B
Lock Detect Output 0 C Disabled
REFout Frequency 0 C Static Low
fVE Output 0 C Disabled
fR Output 0 C Disabled
PLL Reference Oscillator Frequency 10000000 R hz
PLL Tuning Step 5000 R hz
Display/Programmed Freq Difference -10000 hz
Minimum Input Frequency 144000000 hz
Maximum Input Frequency 148000000 hz
Display LPT Line Status 1 Enabled
Printer Port DIN Pin 2
Printer Port ENB Pin 3
Printer Port CLK Pin 4

Notes:

  1. Options with a Register are documented in the MC145170 PLL Data Sheet.
  2. The 'PLL Reference Oscillator Frequency' is divided by 'PLL Tuning Step' to get the R register value.
  3. 'Displayed/Programmed Freq Difference' is added to the displayed frequency to get the frequency programmed into the PLL.  I found that my EXP-1 would be 10khz low on the displayed frequency so this seemed to be the easiest way to address it.
  4. 'Minimum and Maximum Input Frequencies' are used to limit frequency entry to a specific range on the main screen.
  5. When 'Display LPT Line Status' is enabled the DIN, END and CLK line status is displayed on the main screen.  On fast machines it may not be possible to see changes in the line status when the PLL is being programmed.
  6. 'Printer Port DIN Pin, ENB Pin and CLK Pin'  define the printer port pins that are connected to the appropriate PLL pins.  Note that the values are pin numbers on the PC which are not the same as bit numbers.

Set the configuration options as accurately as possible and press F9 to close the configuration screen and save the options.

When back at the main screen enter the frequency you want to program into the PLL. 

Notes on entering frequencies:

  1. Frequencies are entered without decimal points so to get 146.625mhz enter 146625000 and press ENTER.
  2. Frequencies are entered into the Standby frequency, not the Active frequency. 
  3. Press the TAB key to swap the Active and Standby frequencies.