Email: Password: Remember Me | Create Account (Free)

Back to Subject List

Old thread has been locked -- no new posts accepted in this thread
???
12/27/10 21:46
Read: times


 		 #180308 - Partial decoding of external memory...
Dumb question time... :-)

I'm working on a project that will be using one of the Atmel variants of the 8052 (the AT89C52ED2, to be precise...) which has enough internal program and data memory to handle what I intend to do with it. I want to add a memory-mapped LCD interface, but am hoping that I don't need to use an address-latch for the lower eight bits of the address-bus.

If I only have one or two devices mapped into external data-memory, I'm assuming that it's fine to just use the upper 8-bit half of the data bus (Port 2) to select the device, and then just use Port 0 for the data bus...? I'm aware that this will restrict me to putting each device in a 256-byte block - but since it's only going to be two devices *at most*, I don't see a problem with that... as long as I stay away from addresses used by internal memory.

Thoughts...?

List of 76 messages in thread
TopicAuthorDate
Partial decoding of external memory...            01/01/70 00:00      
   8 bit DATA Space            01/01/70 00:00      
      aka "PDATA"            01/01/70 00:00      
   Adres Latch            01/01/70 00:00      
      corrections to all the above replies            01/01/70 00:00      
         Partial decoding of external memory...            01/01/70 00:00      
            There are two locations in the LCD            01/01/70 00:00      
               Re: There are two locations in the LCD            01/01/70 00:00      
                  timing is the reason ...            01/01/70 00:00      
                     one fact expanded            01/01/70 00:00      
                     Thanks for the advice...            01/01/70 00:00      
                        still?            01/01/70 00:00      
                        Maybe it wouldn't hurt to spend time reading the datasheet            01/01/70 00:00      
                           Checking out the Datasheets...            01/01/70 00:00      
                              That's interesting ...            01/01/70 00:00      
                                 Not all BASIC are the same            01/01/70 00:00      
                                    does that apply to BASCOM?            01/01/70 00:00      
                                       "improvements" or extensions?            01/01/70 00:00      
                                          Modern versions of BASIC            01/01/70 00:00      
                                 Re: That's interesting ...            01/01/70 00:00      
                                    Programming on the Fringe            01/01/70 00:00      
                                       Re: Programming on the Fringe            01/01/70 00:00      
                                          To PC or not - but avoid dead ends            01/01/70 00:00      
                                          I'd recommend you think some more about all that            01/01/70 00:00      
                                             That's the key!            01/01/70 00:00      
                                             Brain pollution            01/01/70 00:00      
                                                re: teaching language            01/01/70 00:00      
                                                   Introduce a computer or introduce how to program            01/01/70 00:00      
                                                Initial attraction is fundamental flaw            01/01/70 00:00      
                                    Which concepts do you find particularly hard to grasp?            01/01/70 00:00      
                                       Pointers are normally the main problem when learning C            01/01/70 00:00      
                                          Is the problem specifically 'C', though?            01/01/70 00:00      
                                          pointers aren't unique to 'C'            01/01/70 00:00      
                                             Pointers            01/01/70 00:00      
                                             Big difference in concept - C actually unusual            01/01/70 00:00      
                                                Remember PEEK and POKE            01/01/70 00:00      
                                                Pointers            01/01/70 00:00      
                                                   Pointers and type-safety            01/01/70 00:00      
                                          big problems            01/01/70 00:00      
                                             Wrong direction            01/01/70 00:00      
                                                goes both ways            01/01/70 00:00      
                                       Re: Which concepts do you find particularly hard to grasp?            01/01/70 00:00      
                                          Not a casual subject            01/01/70 00:00      
                                             Re: Not a casual subject            01/01/70 00:00      
                                                I think it's already been said in this thread...            01/01/70 00:00      
                                                one C book should do            01/01/70 00:00      
                                                   Manzi?            01/01/70 00:00      
                                                   It might not hurt to do this in a different sequence            01/01/70 00:00      
                                                   Re: one C book should do            01/01/70 00:00      
                                                      Language matters            01/01/70 00:00      
                                                      you haven't seen ...            01/01/70 00:00      
                                                         Yes, but...            01/01/70 00:00      
                                                            Languages helps but isn't enough            01/01/70 00:00      
                                                         Re: you haven't seen ...            01/01/70 00:00      
                                                            RE: been looking at snippets            01/01/70 00:00      
                                                               Re: been looking at snippets            01/01/70 00:00      
                                                                  Details in standard + compiler manual            01/01/70 00:00      
                                                                      a book doesn't detail everything            01/01/70 00:00      
                                                                     You need to study the compiler documentation            01/01/70 00:00      
                                                                        You need to lean the language first!            01/01/70 00:00      
                                                                           my point was ...            01/01/70 00:00      
                                                                        Re: You need to study the compiler documentation            01/01/70 00:00      
                                                                           Go directly for C            01/01/70 00:00      
                                                                              i second this            01/01/70 00:00      
                                                                              Re: Go Directly to C            01/01/70 00:00      
                                                                                 C support            01/01/70 00:00      
                                                                           the big advantage of PASCAL is            01/01/70 00:00      
                                                                              C isn't that dangerous if caring for compiler warnings            01/01/70 00:00      
                                                                                 So ... C++ is not of interest in this context            01/01/70 00:00      
                                                                                    It's about bracketing claims            01/01/70 00:00      
                                                                                       I did say, "in this context", didn't I?            01/01/70 00:00      
                                                                                          Be careful with your asides!            01/01/70 00:00      
                                                                                          Always give enough context to statements            01/01/70 00:00      
                                                                                             OK ... I stand corrected            01/01/70 00:00      
                                                                                                Separate thread!            01/01/70 00:00      
                                                                                                   I hoped someone would do that            01/01/70 00:00      

Back to Subject List