pad DELAY_ADJ不起作用

我试图在Spartan3A XC3S700A的垫子中使DELAY_ADJ工作。
但似乎通过改变S1，S2，S3无法调节延迟。
附件是FPGA编辑器的截图，其XDL代码如下，
inst“LED0”“IOB”，放置RIOIS_X41Y13 R20，cfg“DELAY_ADJ_ATTRBOX :: VARIABLE DRIVEATTRBOX :: 8 DRIVE_0MA ::＃OFF GTSATTRBOX ::＃OFF IBUF_DELAY_VALUE :: DLY0 ICEINV ::＃OFF ICLK1INV ::＃OFF ICLK2INV ::＃
OFF IDDRIN_MUX :: #OFF IFD_DELAY_VALUE :: DLY0 IFF1 ::＃OFF IFF1_INIT_ATTR ::＃OFF IFF1_SR_ATTR ::＃OFF IFF2 ::＃OFF IFF2_INIT_ATTR ::＃OFF IFF2_SR_ATTR ::＃OFF IFFATTRBOX ::＃OFF IFFDMUX ::＃OFF
IMUX :: 1 IOATTRBOX :: LVCMOS33 IREV_USED ::＃OFF ISR_USED ::＃OFF MISRATTRBOX ::＃OFF MISR_CLK_SELECT ::＃OFF O1INV :: #OFF O1_DDRMUX ::＃OFF O2INV :: O2_B O2_DDRMUX ::＃OFF OCEINV ::
#OFF ODDROUT1_MUX ::＃OFF ODDROUT2_MUX ::＃OFF OFF1 ::＃OFF OFF1_INIT_ATTR ::＃OFF OFF1_SR_ATTR ::＃OFF OFF2 ::＃OFF OFF2_INIT_ATTR ::＃OFF OFF2_SR_ATTR ::＃OFF OFFATTRBOX ::＃OFF OMUX ::
O2 OREV_USED :: #OFF OSR_USED ::＃OFF OTCLK1INV ::＃OFF OTCLK2INV ::＃OFF PCICE_MUX ::＃OFF PCIRDY_MUX ::＃OFF PULL ::＃OFF REVINV ::＃OFF SEL_MUX :: 0 SLEW :: SLOW SRINV
::＃OFF SUSPEND :: 3STATE T1INV :: T1 T2INV ::＃OFF TCEINV ::＃OFF TFF1 ::＃OFF TFF1_INIT_ATTR ::＃OFF TFF1_SR_ATTR ::＃OFF TFF2 ::＃OFF TFF2_INIT_ATTR ::＃OFF TFF2_SR_ATTR：
：#OFF TFFATTRBOX :: #TO TM :: T1 TREV_USED ::＃OFF TSMUX ::＃OFF TSR_USED ::＃OFF T_USED ::＃OFF DELAY_ADJ_BBOX：LED0.DELAY_ADJ：INBUF：IOBUF_inst / IBUF：OUTBUF：IOBUF_inst / OBUFT：
PAD：LED0：“;
任何帮助，将不胜感激...
Ĵ



以下为原文

I tried to make DELAY_ADJ work in a pad in Spartan3A XC3S700A. But it seems that the delay is not adjustable by changing S1, S2, S3. Attached is the screenshot from FPGA editor, and its XDL code is as follows,

inst "LED0" "IOB",placed RIOIS_X41Y13 R20  ,
  cfg " DELAY_ADJ_ATTRBOX::VARIABLE DRIVEATTRBOX::8 DRIVE_0MA::#OFF GTSATTRBOX::#OFF
       IBUF_DELAY_VALUE::DLY0 ICEINV::#OFF ICLK1INV::#OFF ICLK2INV::#OFF
       IDDRIN_MUX::#OFF IFD_DELAY_VALUE::DLY0 IFF1::#OFF IFF1_INIT_ATTR::#OFF
       IFF1_SR_ATTR::#OFF IFF2::#OFF IFF2_INIT_ATTR::#OFF IFF2_SR_ATTR::#OFF
       IFFATTRBOX::#OFF IFFDMUX::#OFF IMUX::1 IOATTRBOX::LVCMOS33 IREV_USED::#OFF
       ISR_USED::#OFF MISRATTRBOX::#OFF MISR_CLK_SELECT::#OFF O1INV::#OFF
       O1_DDRMUX::#OFF O2INV::O2_B O2_DDRMUX::#OFF OCEINV::#OFF ODDROUT1_MUX::#OFF
       ODDROUT2_MUX::#OFF OFF1::#OFF OFF1_INIT_ATTR::#OFF OFF1_SR_ATTR::#OFF
       OFF2::#OFF OFF2_INIT_ATTR::#OFF OFF2_SR_ATTR::#OFF OFFATTRBOX::#OFF
       OMUX::O2 OREV_USED::#OFF OSR_USED::#OFF OTCLK1INV::#OFF OTCLK2INV::#OFF
       PCICE_MUX::#OFF PCIRDY_MUX::#OFF PULL::#OFF REVINV::#OFF SEL_MUX::0
       SLEW::SLOW SRINV::#OFF SUSPEND::3STATE T1INV::T1 T2INV::#OFF TCEINV::#OFF
       TFF1::#OFF TFF1_INIT_ATTR::#OFF TFF1_SR_ATTR::#OFF TFF2::#OFF TFF2_INIT_ATTR::#OFF
       TFF2_SR_ATTR::#OFF TFFATTRBOX::#OFF TMUX::T1 TREV_USED::#OFF TSMUX::#OFF
       TSR_USED::#OFF T_USED::#OFF DELAY_ADJ_BBOX:LED0.DELAY_ADJ: INBUF:IOBUF_inst/IBUF:
       OUTBUF:IOBUF_inst/OBUFT: PAD:LED0: "
  ;

any help would be appreciated...

J