+/** Ternary return type for DMM/LCR/etc packet parser validity checks. */
+enum sr_valid_code {
+ SR_PACKET_INVALID = -1, /**< Certainly invalid. */
+ SR_PACKET_VALID = 0, /**< Certainly valid. */
+ SR_PACKET_NEED_RX = +1, /**< Need more RX data. */
+};
+