请问我可以将哪个引脚用于XC3S50A VQFP100上的DCM时钟？

ug331.pdf pic显示VQFP100中的S350A可以使用引脚83-86,88-90用于DCM。
下面是DCM_X0Y0和DCM_X1Y0。
我根本不明白那张桌子。
所以我用20个时钟做了一个测试项目，所以ISE使用所有全局时钟。
这显示了ISE实施设计的输出。
我给X1Y0加了一个红点。
（CLK10）
X0Y0我在该表中找不到它，它没有被使用。
这来自设计摘要 - 引脚报告。
clk10（红点）放在引脚P41，GCLK15上，即
甚至没有在ug331中列为有效的DCM引脚，但它被称为X1Y0。
那么，我可以将哪个引脚用于XC3S50A VQFP100上的DCM时钟？
编辑：我现在看到DCM_X1Y0和BUFGMUX_X1Y0不是一回事，
但同样的数字让我感到困惑。
当然，我仍然不知道哪些引脚用于DCM。



以下为原文

The ug331.pdf pic shows that S350A in VQFP100 can use pins 83-86, 88-90 for DCM.
Below it says DCM_X0Y0 and DCM_X1Y0.

I don't understand that table at all.

So I've made a test project with 20 clocks, so that ISE uses all global clocks.

This shows the output of ISE Implement Design.
I've put a red dot with X1Y0. (clk10)
X0Y0 I can't find in that table, it is not used.

This is from the Design summary - Pinout report.
clk10 (red dot) is placed on pin P41, GCLK15, which is
not even listed in the ug331 as valid DCM pin, yet it is called X1Y0.

So, which pin(s) may I use for DCM clock on a XC3S50A VQFP100?


edit: I see now that DCM_X1Y0 and BUFGMUX_X1Y0 are not the same thing,
but that same numbers got me confuzed.

Of course, I still don't know which pins to use for DCM.