If the last byte in the read process does not send ACK to the device, the device will not send data. Otherwise, the device will automatically send the byte data of the next address! The previous modification (http://blog.csdn.net/knock/archive/2009/11/02/4758818.aspx) is incorrect. Case master_receive :..... If (g_uiic_pt = g_uiic_datalen) {g_piicreg-> iiccon & = ~ (1 <7); // If you comment it out, the device continues to send data and enters the interrupted status multiple times }..... In general, there are two problems with the modification based on the original version: 1. modify it to the buffer of the driver to receive data on the IIC bus, and copy it to the application's buffer2. modify the iic_ist () in the interrupt service to determine a read or write completion condition if (bdone) {retailmsg (zone_info, (text ("setevent done/R/N"); bdone = false; // Add this setevent (g_htransferdone);} after the modification, my debugging assistant has no errors in reading and writing ~~ Open the camera application. After writing the register of the camera module, the exception 'data abort '(4): thread-id = 01840006 (PTH = 85aa48d4) will no longer appear ), proc-id = 00400002 (PPRC = 82699308) 'nk. EXE ', Vm-active = 04ec0006 (PPRC = 849cda50) 'cmder.exe' Pc = c0b721cc (cost + 0x000021cc) Ra = c0b721b8 (cost + 0x000021b8) sp = d283fe64, BVA = 0004f2cd. However, after the camera application is opened, the first three bytes of the read register are normal and there is ack. The fourth byte read is 0x00, after the camera application is closed, the oscilloscope captures data. Let the problem be solved first, and wait for free before looking for the cause.
