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If you configure the switch for the “Enter” command and press the button, then the current number entry is
actioned by the microcontroller
– the selected frequency register is programmed with the entered number,
stored in EEPROM, and programmed to the Si5351A chip if it is in the active frequency bank.
6.4
ProgRock register configuration
ProgRock contains 29 registers, referred to as Register ID 00 to 28. Each register stores a 32-bit number,
which you can program from the switches and button. The table below lists the register mapping. To enter
a frequency into a register, you must first specify the register, then the required frequency register. The
digits are entered into ProgRock one digit at a time.
You set up a digit on the 4-way DIP switch then press the button briefly. The LED illuminates for a short
time. Wait for the LED to extinguish. Then set up the next digit, press the button, and continue until you
have completely entered all the digits needed. Finally set up the “Enter” code (all 4 switches “on”) and
press the button again. This causes the entered number to be stored at the specified register location.
For example, suppose you wish to set the Clk 0 output in bank 0 to 1.5MHz. The sequence of digits you
need to enter is:
0 4 1 5 0 0 0 0 0 Enter
Because “04” is the register location for Clk 0 Bank 0, and “1500000” is the desired frequency, in Hz. The
total number of digit set-ups and button presses you will need to make, is 10, in this case.
Make sure you give the button a decisive short (brief) press.
Make sure that you wait for the LED to go
out, before pressing the button repeatedly! Button presses are ignored while the LED is
lit. It’s a kind of
very simple switch debounce, as well as an indication of the button press. This is particularly important to
remember if you are
entering a repeated sequence of digits, such as the zeroes in this example. You don’t
need to alter the 4-way DIP switch settings after each digit entry. It is tempting to just keep hitting the
button 5 times, to enter the 5 zeroes. But you MUST WAIT after each button press for the red LED to go
out, first!
If you try to enter a register value into a register number higher than 28, your entry will simply be ignored.
If you enter an invalid frequency, which is to say, the frequency is outside the possible range of the
Si5351A, then the frequency obtained at the output will not be what you want. The most likely output will
be none at all.
At the end of this document is a template which you can print and use to help program the frequencies.
