17.4.4 DMT Count Selection

The Deadman Timer count is set by the DMT count configuration (DMTCNT[4:0]) bits in the Configuration Control Register 2 (CFGCON2) fuse register. The current DMT count value can be obtained by reading the DMT count register DMTCNT.

The PSCNT[31:0] bits in the DMT count post status register (DMTPSCNT) allows the software to read the maximum count selected for the DMT. The PSCNTx bit values are the values that are initially written to the DMTCNTx bits in the CFGCON2 fuse register. Whenever the DMT event occurs, the user can always compare to see whether the current counter value in the DMTCNT register is equal to the value of the DMTPSCNT register, which holds the maximum count value.

Whenever the DMT current counter value in DMTCNT reaches the value of the DMTPSINTV register, the window interval opens permitting the user to execute the DMT clear sequence. The open window interval is indicated by the WINOPN bit in DMTSTAT register.

The UPRCNT[15:0] bits in the DMT hold register (DMTHOLDREG) holds the value of the last read DMT upper count values whenever DMTCNT is last read.