20
6.8
Calibration configuration register, register 28
The value in this register is several smaller numbers, bit-packed into the available 32-bit number. These
parameters control the way the GPS calibration and drift correction processes are done.
In the future I may describe these parameters and their effect. It may be possible to further optimise the
way the calibration and drift correction processes are carried out.
For the time being, just leave this register alone!
6.9
Default frequency output of ProgRock
At switch-on after factory reset, the Clk0 output is set up to default 10.000MHz. Clk1 and Clk2 are
switched off. The reference frequency is set by default to 27.004MHz which should be approximately
c/- 1kHz. Further calibration will be needed for your crystal as described in section 6.6 above.
7. Template for programming ProgRock
On the following page is a template for programming registers in ProgRock. You could print it out and use
it to assist with programming the registers for the frequencies you need.
On the top row is an example. Programming the Bank 0, Clk 0 output to 17.003MHz.
The first two digits are the register number. The register number for the Bank 0, Clk 0 frequency is 04
(refer to the table in section 6.4).
The next 8 digits are the frequency, specified in Hz: 17003000.
Finally, the “Enter” code is input (all 4 switches are “on”).
The ProgRock operator can write out the numbers required, as done here on the top line. Then write the
switch configurations for each digit. Refer to the Binary Coded Decimal table in section 6.3 if necessary.
For each digit, the operator should set the 4 switches of S1 as needed, then press the button briefly (S2). It
will help to write a tick next to the digits which have been input, to avoid forgetting where you are, in the
number.
