Are you in the US or Canada?
I can't find a round/yellow PF cc100, but found a orange/oblong/PF cc200, which is 200 mg Controlled Release
Codeine (Codeine Contin) made by Purdue Frederick,Canada, and a round/blue/PF cc50 which is 50mg, your pill is probably 100mg of the same thing, I can't say for sure, but the odds are in our favor.
I've never heard of CR Codeine.
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