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Hi together I am trying to hook up a LCD and a multiplexer on the c6711DSK -> so I need about 21 digital output lines (write only...) MY QUESTION: Can I connect these devices to the output-pins of J1-connector (40x2 pins) directly, that means without any other TTL-chips...??? and just write through EMIF to this pins, as if there were external RAM...??? If so, do you have some example-code how to initialize EMIF and how to send signal to the J1-connector, respectively how to set on these output-pins individually... Hope, somebody answers... Marko |
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Help...
Started by ●March 26, 2003
Reply by ●March 27, 20032003-03-27
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Dear : I think you should use a buffer between those pins and EMIF,such as 244 and so on. >Hi together > >I am trying to hook up a LCD and a >multiplexer on the c6711DSK -> so I need about 21 digital output >lines (write only...) > >MY QUESTION: >Can I connect these devices to the output-pins of J1-connector (40x2 >pins) directly, that means without any other TTL-chips...??? and just >write through EMIF to this pins, as if there were external RAM...??? > >If so, do you have some example-code how to initialize EMIF and how >to send signal to the J1-connector, respectively how to set on these >output-pins individually... > >Hope, somebody answers... >Marko >_____________________________________ >Note: If you do a simple "reply" with your email client, only the author of this message will receive your answer. You need to do a "reply all" if you want your answer to be distributed to the entire group. > >_____________________________________ >About this discussion group: > >To Join: Send an email to > >To Post: Send an email to > >To Leave: Send an email to > >Archives: http://www.yahoogroups.com/group/c6x > >Other Groups: http://www.dsprelated.com >">http://docs.yahoo.com/info/terms/ > >. Best Regards Jun.Zhou 2003-03-27 |
Reply by ●April 1, 20032003-04-01
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Hiya, I dont think you need to buffer between the J1 or J2 connectors, proving the devices you are using operate between 0 and 5 volts. If you're talking about a buffer to hold the data values that you output, then I don't think you need them. At least, I was messing around with a scope and found logic levels were held on the J1 pins. The dsk uses SN74LVTH162245 between the EMIF and the J1 pins. There is no real need to initialise the EMIF. In my "dsk6xinit.gel" GEL script I have the following lines; ___________ <Some stuff> *(int *)EMIF_GCTL = 0x00003040; /* EMIF global control register*/ *(int *)EMIF_CE1 = 0xFFFFFF23; /* CE1 - 32-bit asynch access after boot*/ *(int *)EMIF_CE0 = 0xFFFFFF30; /* CE0 - SDRAM*/ *(int *)EMIF_CE2 = 0x00000023; /* CE2 - 32-bit asynch on daughterboard (def 41)*/ *(int *)EMIF_CE3 = 0x00000023; /* CE3 - 32-bit asynch on daughterboard (def 41)*/ *(int *)EMIF_SDRAMCTL = 0x07117000; /* SDRAM control register (100 MHz)*/ *(int *)EMIF_SDRAMTIMING = 0x0000061A; /* SDRAM Timing register */ *(int *)EMIF_SDRAMEXT = 0x00054519; /* SDRAM Extension register */ <some stuff> ___________ CE2 is the address space you will want to use - it starts at 0xA000000, I've just set mine up so that it has 0 wait states (needed to allow data to stabilise on the lines when reading/writing to external devices) As you want 21 lines, you can connect data lines ED0 to ED20 up to your LCD and multiplexor and ground the rest of them. If your devices need synchronisation of any sort with a clock etc, then the relevant lines can be set up, and changes made in the EMIF_CE2 register. Test your connections using a Memory View window in ccs. then in code #define LCD_MUX_ON_J1 0xA0000000 you would write your output as if it were to a normal address location *(int*)LCD_MUX_ON_J1 = 0x00000043; (I think it's the same format as above GEL code) Note that this mirrors the value 0x00000043 to all addresses in the range 0xA0000000 -> 0xBFFFFFFF Adam ----- Original Message ----- From: "Jesse.Zhou" <> Subject: Re: [c6x] Help... > Dear : > > I think you should use a buffer between those pins and EMIF,such as 244 and so > on. > > >Hi together > > > >I am trying to hook up a LCD and a > >multiplexer on the c6711DSK -> so I need about 21 digital output > >lines (write only...) > > > >MY QUESTION: > >Can I connect these devices to the output-pins of J1-connector (40x2 > >pins) directly, that means without any other TTL-chips...??? and just > >write through EMIF to this pins, as if there were external RAM...??? > > > >If so, do you have some example-code how to initialize EMIF and how > >to send signal to the J1-connector, respectively how to set on these > >output-pins individually... > > > >Hope, somebody answers... > >Marko |
