39/43

STA016A

(the INTLINE[0] pin).

8.0.1

Reading a request from mmdsp :

MMDSP write its request inside dedicated host registers (mainly H70 to H78 and H134 to H169), then it signals

to cd_module that it must read a request by sending the interrupt IT_REQ.

Note that IT_REQ interrupt is generated by mmdsp on the IRQB pin of STA016A.

Note also that once it has finished to read the message, cd_module must always acknowledge it by reading

H10.

Figure 7. Block diagram for running the CD application.

power on

cd

inserted ?

no

wait IT_REQ

with 35 in H70

start cd-rom application:

write 0 in H85, then 1 in H86

send play_music command :

write 112 in H64

send IT_CMD

wait IT_REQ

with 112 in H70

any

command?

cd

ejected?

run other

application?

send pause command :

write 2 in H64

send IT_CMD

run the other

application

no

yes

yes

return

to cd?

no

yes

send other command :

write in H64

send IT_CMD

Hxx: host register

number xx

write 1 in SOFT_RESET

write 0 in CK_CMD