Samsung S5PC100 User Manual page 1722

S5PC100 USER'S MANUAL (REV1.0)
4.6 SHADOWED REGISTER
Both SPDBSTAS_SHD register and SPDCNT_SHD register are shadowed registers which are related to
SPDBSTAS register and SPDCNT register, respectively. They are updated from related registers every stream
end interrupt signal. Their usage is as follows.
1. Sets burst status and repetition count information to their respective registers.
2. Turns on SPDIF module, and stream end interrupt is asserted immediately.
3. With stream end interrupt, shadowed registers are updated from their related registers and SPDIF data starts
to go out. Now next stream information (burst status and repetition count) is written to SPDBSTAS and
SPDCNT register because previous information is copied to their respective shadowed registers.
4. Set next stream information to SPDBSTAS and SPDCNT register.
5. Wait for stream end interrupt which signals the end of the first stream.
6. With stream end interrupt, the 2
The usage of user bit registers is similar to that of stream information registers except that they are not related to
SPDIF end interrupt but to user data interrupt. As soon as SPDIF is on, shadowed user bit registers are updated
from their related registers and user bit starts to be shifted out with user data interrupt asserted. User can write
the next user data to registers with this interrupt. After all of the 96 user bits are shifted out, user data interrupt
asserts again and 3rd user bits is written to registers with 2nd user bits going out.
nd
stream data starts to go out. Sets 3
SPDIF TRANSMITTER
rd
stream information to registers.
10.6-7