PP_STAT_BSY
#define RXDATA PP_STAT_BSY /* Rx Input Data, channel 0. 0 0 0 */
#define SYNC_DATA PP_STAT_BSY /* Reserved - Sync Data. 0 1 0 */
#define DATA_ECHO PP_STAT_BSY /* Parallel Port Data Echo. 1 0 0 */
#define A0_ECHO PP_STAT_BSY /* Address 0 Echo. 1 0 1 */
#define A1_ECHO PP_STAT_BSY /* Address 1 Echo. 1 1 0 */
#define A2_ECHO PP_STAT_BSY /* Address 2 Echo. 1 1 1 */