time detection via WWVB and the CME8000 module

I am attempting to provide automated time detection via the WWVB signal
for embedded logging devices. I want to be able to time/date stamp data
collection without requiring the user to set it manually. The CME8000
is a receiver chip that seems ideal. I have purchased and powered up
the CME8000-BUS-LP-01 module (easily available form Digi-Key). This
module uses one of the most bizarre protocols I have ever seen- a
mishmash of IIC, RS232, and others. The data *** is also one of the
worst I've ever seen, requiring inference and extrapolation to figure
out how the thing actually works. The purpose of this long-winded post
is to ask if anyone else has used this device, and figured out how to
generate the CRC bytes required by the protocol. I have contacted C-MAX
(a chinese company), their domestic rep, and tech suport at DigiKey,
all to no avail. I have tried CRC16, CRCITT, (and their reverse
polynomials), msb-lsb and lsb-msb ordering of crc bytes without being
able to communicate to this opaque device. The pdf document
CME8000-BUS-B6.pdf) I downloaded from their site refers to sample
source code in the appendix- the appendix doesn't exist. If anyone has
cracked the CRC algorithm I would be very grateful for any help.

TIA
Harry Sieber
Sieber Consulting

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