peb20560 Infineon Technologies Corporation, peb20560 Datasheet - Page 162

• Manufacturer Part Number: peb20560
• Description: Dsp Oriented Pbx Controller Doc
• Manufacturer: Infineon Technologies Corporation

Semiconductor Group
Data Transfer from the µP to the OAK
• The µP tests the MBUSY bit.
• The µP writes to the data registers (optional).
• The µP writes to the µP-command register (MCMD) (must be performed) - this write
• An OAK interrupt (INT2) is activated due to the write to the command register.
• The OAK INT2 routine reads MCMD and performs the command (the read of the
• If the command is asking for data (like a read of an OAK register), the interrupt routine
• When finished, the INT2 routine resets MBUSY for enabling the µP to send the next
The µP can write consecutive writes to the µP mailbox and it’s up to the user to make
sure that the data has been transferred to the OAK correctly (the busy bit has been reset)
before writing new data to the µP mailbox.
2.10.2
The OAK mailbox includes:
• Six general purpose 16-bit registers (ODTx)
• An 8-bit command register (OCMD)
• One bit busy register (OBUSY). All the registers can be written by the OAK and read
A write of the OAK to the OAK mailbox command register generates an interrupt to the
µP (INT Source No.6). Therefore, when the user wants to transfer more data then the
command register must be written last.
A busy bit (OBUSY) which can be read by the OAK is set automatically after a write of
the OAK to the OAK command register and is reset by a direct µP write to it (when the
µP has finished reading the OAK mail box contents).
Users can define own opcodes (up to 256 opcodes) for the transfer direction from the
OAK to the µP.
Data Transfer from the OAK to the µP
• The OAK tests the OBUSY bit.
• The OAK writes to the data registers (optional).
• The OAK writes to the command register (OCMD) (must be performed). This write
• A µP interrupt is activated due to the write operation to the command register.
• The µP reads the command register and performs the command.
• If the command is asking for data (like a read of a µP register), the interrupt routine
sets automatically the
command register stops the INT2 activation automatically).
puts the data in the OAK mailbox registers.
command.
by the µP.
operation sets the OAK mailbox busy bit (OBUSY).
puts the data in the µP mailbox registers.
OAK Mailbox
µ
P mailbox busy bit (MBUSY).
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Functional Block Description
PEB 20560
2003-08