UART Environments
12-16
12.2.5 Switching Procedures
The following procedures enable you to switch from MPU to DSP.
For switching UART1 to DSP:
1) MPU: Write 0 into the UART1 TIPB switch configuration MPU register
(RHSW_ARM_CNF) to unlock UART1.
2) DSP: Write 2 into the UART1 TIPB switch status DSP register
(RHSW_DSP_CNF) to lock UART1.
For switching UART2 to DSP:
1) MPU: Write 0 into the UART2 TIPB switch configuration MPU register
(RHSW_ARM_CNF) to unlock UART2.
2) DSP: Write 2 into UART2 TIPB switch configuration DSP register
(RHSW_DSP_CNF) to lock UART2.
For switching UART3 to DSP:
1) MPU: Write 0 into the UART3 TIPB switch configuration MPU register
(RHSW_ARM_CNF) to unlock UART3.
2) DSP: Write 2 into UART3 TIPB switch configuration DSP register
(RHSW_DSP_CNF) to lock UART3.
Note:
PERIF_LOCK Bits
If either the DSP_PERIF_LOCK (in the RHSW_DSP_CNF register) or the
ARM_PERIF_LOCK bit (in the RHSW_ARM_CNF register) is already set to
1, then a write to the other PERIF_LOCK bit has no effect on the TIPB
switches, even though such a write may be performed. Before attempting to
write 1 to a PERIF_LOCK bit, the DSP and MPU software must always read
the corresponding read-only PERIF_LOCK bits to confirm that the other
processor PERIF_LOCK bit is not already set.