SLAZ283AA October 2012 – May 2021 MSP430F5435
JTAG Module
Debug
JTAG mailbox handshake mechanism can go out of sync.
The JTAG mailbox handshake mechanism can go out of sync, if the CPU accesses the Mailbox (read or write on JMB data registers) while the JMBOUTCTL/JMBIBCTL register is accessed via the JTAG interface.
- Avoid reading or writing on JMB data registers by CPU while the JMBOUTCTL/JMBIBCTL register is accessed via the JTAG interface.
or
- Send a request (set OUTREQ or INPREQ bit in JMBINCTL register) only when it can be served immediately. This means in detail:
INPUT: Wait until the the input registers are empty (IN0RDY = IN1RDY = 1) before sending an input request (INPREQ = 1) to the JMBINCTL register.
OUTPUT 16 Bit: Wait until the CPU has written Register JMBOUT0 (OUT0RDY = 1) before sending an output request (OUTREQ = 1) to the JMBINCTL register.
OUTPUT 32 Bit: Wait until the CPU has written Registers JMBOUT0 and JMBOUT1 (OUT0RDY = OUT1RDY = 1) before sending an output request (OUTREQ = 1) to the JMBINCTL register.