很诡异的问题，一个DRC警告，WARNING

WARNING [DRC0004]   Possible pin type conflict U1,IO_VB7N0_W15 Bidirectional Connected to Output Port:  FPGA, PAGE-A1DR FPGA END  (2.50, 5.30)
请看图

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Checking Schematic: FPGA
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Checking Electrical Rules
WARNING [DRC0004]   Possible pin type conflict U1,IO_VB6N1_V21 Bidirectional Connected to Output Port:  FPGA, PAGE-A1DR FPGA END  (4.90, 2.20)
WARNING [DRC0004]   Possible pin type conflict U1,IO_VB7N0_AA19 Bidirectional Connected to Output Port:  FPGA, PAGE-A1DR FPGA END  (5.00, 4.80)
WARNING [DRC0004]   Possible pin type conflictWARNING [DRC0004]   Possible pin type conflict U1,IO_VB7N0_W15 Bidirectional Connected to Output Port:  FPGA, PAGE-A1DR FPGA END  (2.50, 5.30)  U1,IO_VB7N0_Y14 Bidirectional Connected to Output Port:  FPGA, PAGE-A1:DDR FPGA END  (2.50, 5.50)
WARNING [DRC0004]   Possible pin type conflict U1,IO_VB6N1_V20 Bidirectional Connected to Output Port:  FPGA, PAGE-A1:DDR FPGA END  (4.90, 2.10)
WARNING [DRC0004]   Possible pin type conflict U1,IO_VB6N1_V22 Bidirectional Connected to Output Port:  FPGA, PAGE-A1:DDR FPGA END  (4.90, 2.30)
WARNING [DRC0004]   Possible pin type conflict U1,IO_VB6N1_W22 Bidirectional Connected to Output Port:  FPGA, PAGE-A1:DDR FPGA END  (4.90, 2.70)
WARNING [DRC0004]   Possible pin type conflict U1,IO_VB7N0_W16 Bidirectional Connected to Output Port:  FPGA, PAGE-A1:DDR FPGA END  (2.50, 5.40)
WARNING [DRC0004]   Possible pin type conflict U1,IO_VB7N0_AB18 Bidirectional Connected to Output Port:  FPGA, PAGE-A1:DDR FPGA END  (5.00, 5.60)
WARNING [DRC0004]   Possible pin type conflict U1,IO_VB7N0_Y17 Bidirectional Connected to Output Port:  FPGA, PAGE-A1:DDR FPGA END  (2.50, 5.60)
WARNING [DRC0004]   Possible pin type conflict U1,IO_VB6N1_Y21 Bidirectional Connected to Output Port:  FPGA, PAGE-A1:DDR FPGA END  (4.90, 3.10)
WARNING [DRC0004]   Possible pin type conflict U1,IO_VB6N1_Y22 Bidirectional Connected to Output Port:  FPGA, PAGE-A1:DDR FPGA END  (4.90, 3.20)
WARNING [DRC0004]   Possible pin type conflict U1,IO_VB7N0_AA18 Bidirectional Connected to Output Port:  FPGA, PAGE-A1:DDR FPGA END  (5.00, 4.70)
WARNING [DRC0004]   Possible pin type conflict U1,IO_VB6N1_W21 Bidirectional Connected to Output Port:  FPGA, PAGE-A1:DDR FPGA END  (4.90, 2.60)
WARNING [DRC0004]   Possible pin type conflict U1,IO_VB7N0_AB19 Bidirectional Connected to Output Port:  FPGA, PAGE-A1:DDR FPGA END  (5.00, 5.70)
WARNING [DRC0004]   Possible pin type conflict U1,IO_VB6N1_R17 Bidirectional Connected to Output Port:  FPGA, PAGE-A1:DDR FPGA END  (4.90, 1.70)

這個很正常啊，例如有些芯片的管腳在手冊上說是 Bidirectional，可是它有很多模式可以選擇，好比說 GPIO INPUT、GPIO OUTPUT、UART TX，這時候你在ORCAD建立元件庫的時候，你可能選擇 Bidirectional ，可是實際上你可能是一個 GPIO INPUT PIN，所以會接某元件的 OUTPUT PIN，所以 ORCAD 會提醒你 Bidirectional Connected to Output Port。
所以在件元件庫的時候，要慎選 PIN TYPE。另外一個方法是去修改， ERC Matrix 的規則，只怕 98%Bidirectional Connected to Output Port 是沒關係的，其他 2% 是真正有問題，如果沒仔細看，有時候會很淒慘的啦~~~~~~

仔细看，我试着把那个PIN 没连接到任何网络，都会出现那个警告。
百思不得其解啊

解决问题，把PORT 改成off-page 就OK
虽然逻辑上说不清楚。

怎會說不清楚。請看別人的帖子 http://www.eda365.com/thread-9218-1-1.html
帖子還是放在 [推薦主題] ，非常醒目呢。

我的port确信属性没问题的~~所以说不清楚嘛