cf卡交流 交流

angy670

altera 上相关信息是：
Nios II processor version 5.0 includes a Compact Flash controller peripheral suitable for interfacing to Compact Flash cards in True IDE mode on Nios development boards. In order for True IDE mode to operate, Compact Flash cards require that the "ATASEL_N" input be driven to ground during power-up.

The Compact Flash controller peripheral includes a configurable power register used to power-cycle Compact Flash cards in Nios II software through a MOSFET on the Nios development boards. However, in certain development boards, power to the Compact Flash card will not be turned off completely during this power-cycle operation. Because of this, the "ATASEL_N" pin may not be sampled during the power-cycle operation after FPGA configuration when this pin is driven to ground. Instead, "ATASEL_N" may be sampled by the Compact Flash card when power is first applied to the development board, when I/O are not yet driven by the FPGA (before FPGA configuration).

Workaround:  If you encounter errors with Compact Flash when using the Nios development boards, please try one of the following workarounds:

Try a different Compact Flash card -- Certain cards are more susceptible to the power-cycling issue than others.
Modify the Nios development board -- This is recommended for users who are familiar and comfortable with board-level modifications. Disconnect pin 9 (ATASEL_N) on the Compact Flash socket on your Nios Development Board and tie this pin to ground. Note that the Compact Flash socket uses a staggered numbering on the pins (starting from pin 1: 1, 26, 2, 27, ...); please refer to the Compact Flash Association specification for right-angle surface-mount connectors for exact specifications on this connector. Caution: This will permanently enable True-IDE mode operation.

[此贴子已经被作者于2005-8-28 15:53:37编辑过]

angy670

我用的是ep2c35板子
在调试cf卡程序时碰到几个问题
想跟熟悉cf卡的朋友交流交流

我用的是nios 论坛上的那个测试程序
的出的结果是：
IDE_initialize(): error: verify fail: wrote 0x0, read 0xFF
IDE_initialize(): error: verify fail: wrote 0x1, read 0xFF
IDE_initialize(): error: verify fail: wrote 0x2, read 0xFF
IDE_initialize(): error: verify fail: wrote 0x3, read 0xFF
IDE_initialize(): error: verify fail: wrote 0x4, read 0xFF
IDE_initialize(): error: verify fail: wrote 0x5, read 0xFF
IDE_initialize(): error: verify fail: wrote 0x6, read 0xFF
IDE_initialize(): error: verify fail: wrote 0x7, read 0xFF
IDE_initialize(): error: verify fail: wrote 0x8, read 0xFF
IDE_initialize(): error: verify fail: wrote 0x9, read 0xFF
IDE_initialize(): error: failed register write/readback test.
Cannot initialize IDE device.

请高人指点指点
这是nios论坛上人讲的：
      it stems from the fact that to operate in True IDE mode, CF cards need their atasel_n pin driven low at power-up. Since atasel_n is an FPGA I/O, and the FPGA's I/O are tri-stated before FPGA configuration, we need to power-cycle the compact flash cards from Nios during the boot process to ensure that the CF card initializes correctly. However, compact flash cards from certain manufactuerers exhibit significant leakage current. This causes them not to be powered off completely when the CF power register bit in the CF peripheral is cycled by the Nios II CPU, and as such, the atasel_n input isn't sampled again as happens during the power on process.

我们应该怎么确保atasel在启动是变低电频呢
这难道不是板子自己处理吗？？
我的qq是：53579621
email：wjbzl@hotmail.com

我测试cf卡时
读任何寄存器结果都是0xff呢
即使我先往寄存器里写别的数字

[此贴子已经被作者于2005-8-28 20:55:19编辑过]