Hi! I am learning ide driver based on AU1200 and the kernel is 2.6.11.The CROSS_COMPILE I used is gcc-3.3.5-glibc-2.3.2/mipsel-unknown-linux-gnu.When the ide driver used RCS2 controller, it worked well.But when i change to use RCS1 controler,it didn't work.The both register MEM_STCFG and MEM_STTIME are set same: MEM_STCFG 0xfe2401c6 MEM_STTIME 0x7f7ffc3f.I set the time to max for testing.The RCS2 io_base is 0x18000000,the RCS1 io_base is 0x0c000000.So I set MEM_STADDR1 to 0x10c03f00. I used the fallowing codes for testing: while(1){ au_writeb(0xff,0xac000000); } I can't see any singal,such as CS,WE,DATA.But I added "udelay(4);" in the while circle or just change au_writeb to au_readb(0xac000000),I counld see all the signal is right(has signal).The testing codes as fallow: while(1){ au_readb(0xac000000); } and while(1){ udelay(4); au_writeb(0xff,0xac000000) } In the testing,the IDE is not connected,as I just want to test the signal is good or not. Could someone tell me what wrong it is?Is there any different init setting between RCS1 and RCS2?How I could make the RCS1 work? I also come to the U-boot(U-boot1.1.4) to do the same testing after the reset.The result is same. reset: #if 1 li t0, 0xb4001018 /*cs1 addr reg*/ li t1, 0x00 sw t1, 0(t0) li t0, 0xb4001010/*cfg reg*/ li t1, 0xfe2401c6 sw t1, 0(t0) li t0, 0xb4001014/*timer reg*/ li t1, 0x7f7ffc3f sw t1, 0(t0) li t0, 0xb4001018 li t1, 0x10c03f00 sw t1, 0(t0) loop: li t0, 0xac000000 li t1, 0xff sb t1, 0(t0) b loop #endif /*for test lzcx add*/ The test changing to CS2 control is good. Thanks for your help in advance. Mr.liang