PRELIMINARY
S3C6400X RISC MICROPROCESSOR
HOST INTERFACE
24-11
Preliminary product information describe products that are in development,
for which full characterization data and associated errata are not yet available.
Specifications and information herein are subject to change without notice.
Mailbox Interface
The modem can use a 32-bit in-mailbox and a 32-bit out-mailbox for IPC (Inter Process Communication)
between the modem and the AP (S3C6400).
Mailbox basic operation
When the modem writes a 32-bit data into the in-mailbox, the CPUIF Client generates an interrupt to the AP
(S3C6400)’s CPU so that the AP (S3C6400)’s CPU will read the in-mailbox to know the requests from the
modem. The format of the in-mailbox can be freely defined by the application. The in-mailbox flag in the CPUIF
Client is automatically cleared when the AP (S3C6400)’s CPU reads the in-mailbox.
When the AP (S3C6400)’s CPU writes a 32-bit data into the out-mailbox, the CPUIF Client generates an
interrupt to the modem so that the modem will read the out-mailbox to know the requests from the AP
(S3C6400)’s CPU. The format of the out-mailbox can be freely defined by the application. The out-mailbox flag
(ie, STAT1 [0]) in the CPUIF Client is automatically cleared when the modem reads the out-mailbox.
Interrupt
Controller
CPUIF_CLIENT
S3C6400 (AP)
External
Modem
IMB_EMPTY
OMB_FILLED
Internal
Memory
IMB_FILLED
OMB_EMPTY
- STAT1[15:0]
- INTE1[15:0]
- CPUIFC_STAT2[15:0]
- CPUIFC_INTE2[15:0]
INTR
IRQ
a 32-bit OMB
a 32-bit IMB
Master 1
Slave
Modem(Host)
Interface
Peri Bus
Master 0
External
Memory
Controller
Syst
em
Bus (
T
o
Extern
al Mem
o
ry)
Figure
24-11. In/Out Mailbox between Modem and AP