if (period < 8)
                period = 8;
        if (period < 10) {
-               ppr_options |= MSG_EXT_PPR_DT_REQ;
-               if (period == 8)
-                       ppr_options |= MSG_EXT_PPR_IU_REQ;
+               if (spi_max_width(starget)) {
+                       ppr_options |= MSG_EXT_PPR_DT_REQ;
+                       if (period == 8)
+                               ppr_options |= MSG_EXT_PPR_IU_REQ;
+               } else
+                       period = 10;
        }
 
        dt = ppr_options & MSG_EXT_PPR_DT_REQ;
                printf("%s: %s DT\n", ahd_name(ahd), 
                       dt ? "enabling" : "disabling");
 #endif
-       if (dt) {
+       if (dt && spi_max_width(starget)) {
                ppr_options |= MSG_EXT_PPR_DT_REQ;
                if (!width)
                        ahd_linux_set_width(starget, 1);
                       iu ? "enabling" : "disabling");
 #endif
 
-       if (iu) {
+       if (iu && spi_max_width(starget)) {
                ppr_options |= MSG_EXT_PPR_IU_REQ;
                ppr_options |= MSG_EXT_PPR_DT_REQ; /* IU requires DT */
        }
                       rdstrm  ? "enabling" : "disabling");
 #endif
 
-       if (rdstrm)
+       if (rdstrm && spi_max_width(starget))
                ppr_options |= MSG_EXT_PPR_RD_STRM;
 
        ahd_compile_devinfo(&devinfo, shost->this_id, starget->id, 0,
                       wrflow ? "enabling" : "disabling");
 #endif
 
-       if (wrflow)
+       if (wrflow && spi_max_width(starget))
                ppr_options |= MSG_EXT_PPR_WR_FLOW;
 
        ahd_compile_devinfo(&devinfo, shost->this_id, starget->id, 0,
                       rti ? "enabling" : "disabling");
 #endif
 
-       if (rti)
+       if (rti && spi_max_width(starget))
                ppr_options |= MSG_EXT_PPR_RTI;
 
        ahd_compile_devinfo(&devinfo, shost->this_id, starget->id, 0,
                       pcomp ? "Enable" : "Disable");
 #endif
 
-       if (pcomp) {
+       if (pcomp && spi_max_width(starget)) {
                uint8_t precomp;
 
                if (ahd->unit < ARRAY_SIZE(aic79xx_iocell_info)) {
        unsigned int dt = ppr_options & MSG_EXT_PPR_DT_REQ;
        unsigned long flags;
 
-       if (hold)
+       if (hold && spi_max_width(starget))
                ppr_options |= MSG_EXT_PPR_HOLD_MCS;
 
        ahd_compile_devinfo(&devinfo, shost->this_id, starget->id, 0,
 
 
        if (period < 9)
                period = 9;     /* 12.5ns is our minimum */
-       if (period == 9)
-               ppr_options |= MSG_EXT_PPR_DT_REQ;
+       if (period == 9) {
+               if (spi_max_width(starget))
+                       ppr_options |= MSG_EXT_PPR_DT_REQ;
+               else
+                       /* need wide for DT and need DT for 12.5 ns */
+                       period = 10;
+       }
 
        ahc_compile_devinfo(&devinfo, shost->this_id, starget->id, 0,
                            starget->channel + 'A', ROLE_INITIATOR);
        unsigned long flags;
        struct ahc_syncrate *syncrate;
 
-       if (dt) {
+       if (dt && spi_max_width(starget)) {
                ppr_options |= MSG_EXT_PPR_DT_REQ;
                if (!width)
                        ahc_linux_set_width(starget, 1);