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Hi, I have interfaced a MPC850 (power pc ) to a 21065L Rev 0.3 via a FPGA. I can inspect all I/O registers in the host port from the PowerPC. I am having trouble loading a boot program into the DSP through the host port. Several points do not add up when checking and writing to the host port according to the manual. I can read and change the registers without problems, such as I can set the syscon register for 32bit bus, reset the dsp and toggle the bus hang bit etc. In the fpga I have set it up so that when I write to the highest bit of the I/O host port 0 it opens up the channel to the DSP which means HBR will remain low until I write a zero to the highest bit of the I/O host port 0. 1) I have checked all hardware lines several times to ensure it is setup for host boot but when I look at the EPB0 registers I find the following: IIEP0 = 0000 IMEP0 = 01 CEP0 = 0x100 EIEP0 = 0x8000 0000 EMEP0 = 0x1 ECEP0 = 0x600 This looks more like the setup for no boot mode? and I believe the IIEP0 should be 0x8000. 2) The DMAC8 appears to be setup correctly for Instructions, 16 to 48 bit packing and DMA on. 3) I find I that I need to set the Buffer Hang Inhibit before writing to the EPB0 register otherwise I observe some very strange behaviour. If I write to the EPB0 without setting the BHD bit then all of the 255 registers show up as the value I have just written to the EPB0 register. If I set the BHD bit then this does not occur. 3) After setting the BHD bit to 1, If I setup the IIEP0 to 0x8000 then I manually write a single 32 bit value to the EPB0 I find that the IIEP0 will increment in value up to 0x800A as if 10 words have been written to the EPB0 which is not the case. 4) Note: I can read and write all other registers without any problem, for example, I can read the flags Inputs and change them to outputs without any problem. 5) I have tried different packing modes such as no packing, 16 to 32 bit packing etc. 6) If I enable EPB1 (DMA 9) I find I have the same problem. PS: I have had the DSP running code through its JTAG port without any problems. I believe untill I resolve the problem above I will not be able to program the DSP through the Host port can anyone offer any suggestions? Regards David D David Dart (Senior Systems Engineer) Nu-Lec Industries (ACN 085 972 425) 35-37 South Street, Lytton, Brisbane, Qld, 4178, Australia P.O. Box 761, Edith Street, Wynnum, Qld, 4178, Australia Direct Dial Phone No: +61 7 3249 5424 Switchboard Phone No: +61 7 3249 5444 Facsimile No: +61 7 3249 5888 Email Address: World Wide Web Site: http://www.nulec.com.au |
Botting through host interface port on 21065L
Started by ●September 5, 2001
