-\r
-/**\r
- * Function tap_state_transition\r
- * takes a current TAP state and returns the next state according to the tms value.\r
- *\r
- * Even though there is code to duplicate this elsewhere, we do it here a little\r
- * differently just to get a second opinion, i.e. a verification, on state tracking\r
- * in that other logic. Plus array lookups without index checking are no favorite thing.\r
- * This is educational for developers new to TAP controllers.\r
- */\r
-static tap_state_t tap_state_transition(tap_state_t cur_state, int tms)\r
-{\r
- tap_state_t new_state;\r
-\r
- if (tms)\r
- {\r
- switch (cur_state)\r
- {\r
- case TAP_RESET:\r
- new_state = cur_state;\r
- break;\r
- case TAP_IDLE:\r
- case TAP_DRUPDATE:\r
- case TAP_IRUPDATE:\r
- new_state = TAP_DRSELECT;\r
- break;\r
- case TAP_DRSELECT:\r
- new_state = TAP_IRSELECT;\r
- break;\r
- case TAP_DRCAPTURE:\r
- case TAP_DRSHIFT:\r
- new_state = TAP_DREXIT1;\r
- break;\r
- case TAP_DREXIT1:\r
- case TAP_DREXIT2:\r
- new_state = TAP_DRUPDATE;\r
- break;\r
- case TAP_DRPAUSE:\r
- new_state = TAP_DREXIT2;\r
- break;\r
- case TAP_IRSELECT:\r
- new_state = TAP_RESET;\r
- break;\r
- case TAP_IRCAPTURE:\r
- case TAP_IRSHIFT:\r
- new_state = TAP_IREXIT1;\r
- break;\r
- case TAP_IREXIT1:\r
- case TAP_IREXIT2:\r
- new_state = TAP_IRUPDATE;\r
- break;\r
- case TAP_IRPAUSE:\r
- new_state = TAP_IREXIT2;\r
- break;\r
- default:\r
- LOG_ERROR( "fatal: invalid argument cur_state=%d", cur_state );\r
- exit(1);\r
- break;\r
- }\r
- }\r
- else\r
- {\r
- switch (cur_state)\r
- {\r
- case TAP_RESET:\r
- case TAP_IDLE:\r
- case TAP_DRUPDATE:\r
- case TAP_IRUPDATE:\r
- new_state = TAP_IDLE;\r
- break;\r
- case TAP_DRSELECT:\r
- new_state = TAP_DRCAPTURE;\r
- break;\r
- case TAP_DRCAPTURE:\r
- case TAP_DRSHIFT:\r
- case TAP_DREXIT2:\r
- new_state = TAP_DRSHIFT;\r
- break;\r
- case TAP_DREXIT1:\r
- case TAP_DRPAUSE:\r
- new_state = TAP_DRPAUSE;\r
- break;\r
- case TAP_IRSELECT:\r
- new_state = TAP_IRCAPTURE;\r
- break;\r
- case TAP_IRCAPTURE:\r
- case TAP_IRSHIFT:\r
- case TAP_IREXIT2:\r
- new_state = TAP_IRSHIFT;\r
- break;\r
- case TAP_IREXIT1:\r
- case TAP_IRPAUSE:\r
- new_state = TAP_IRPAUSE;\r
- break;\r
- default:\r
- LOG_ERROR( "fatal: invalid argument cur_state=%d", cur_state );\r
- exit(1);\r
- break;\r
- }\r
- }\r
-\r
- return new_state;\r
-}\r