| ??? 12/09/05 21:29 Read: times |
#105003 - So, how are they connected? Responding to: ???'s previous message |
Edgardo Gonzalez said:
here you go ..
http://people.morrisville.edu/~gonzal46/lab7.bmp there connected to an 8 bit switch module Ok, but how are they connected? This isn't on your schematic! It's imperative that you connect the switches properly, and use proper pull-ups/pull-downs as appropriate. This applies regardless of whether the switches are discrete or part of a module. Note also that switches usually require some sort of debouncing to function reliably as microprocessor inputs. and i see no activity, absolutly no movement at the /OE's of the tristate buffer when a switch was active That's a big problem right there. If you're not seeing that, there is absolutely no chance the switch data is going to make it into the microcontroller. Are you sure you didn't miss it? Remember, it's going to be quite brief. I would suggest you set your scope to trigger once on a falling edge of the /OE and then try a read operation. also, this is while this SIMPLE program is running in terminal (basic)
10 a=xby(58000) 20 p.a 30 goto 10 this is what i see ... 0 0 0 0 0 0 0 0 Then i stop the program .... even when switches are pressed it still says zero Hmm, basic. I've never done this before, but I assume the first line is attempting to read from xdata location 0d58000. Is this in fact what that does? From your schematic, I am under the impression that your switches will be accessed whenever you read from xdata address 0b1110 0xxx xxxx xxxx. Thus, 0d58000 seems like a reasonable address from which to read. So, you really need to track down that /OE pulse. --Sasha Jevtic |
| Topic | Author | Date |
| 8052 with a decoder - help! | 01/01/70 00:00 | |
| in addition .. | 01/01/70 00:00 | |
| can not work ! | 01/01/70 00:00 | |
| Program store? | 01/01/70 00:00 | |
| 8052 with a decoder - not a -31 | 01/01/70 00:00 | |
| im sorry :( | 01/01/70 00:00 | |
| if the problem you refer to is no code m | 01/01/70 00:00 | |
| ok | 01/01/70 00:00 | |
| The ground pin | 01/01/70 00:00 | |
| Yes, there are problems | 01/01/70 00:00 | |
| grounded | 01/01/70 00:00 | |
| picture | 01/01/70 00:00 | |
| No picture | 01/01/70 00:00 | |
| thoguht so .. | 01/01/70 00:00 | |
| Tristate latch output enable | 01/01/70 00:00 | |
| YOU ARE GOD! | 01/01/70 00:00 | |
| i am curious .. | 01/01/70 00:00 | |
| Welcome to embedded systems | 01/01/70 00:00 | |
| Thanks A Lot | 01/01/70 00:00 | |
| WHAT memory??? | 01/01/70 00:00 | |
| RAM | 01/01/70 00:00 | |
| it is .. | 01/01/70 00:00 | |
| another pic | 01/01/70 00:00 | |
| Another bad picture | 01/01/70 00:00 | |
| updated schematic | 01/01/70 00:00 | |
| AIM | 01/01/70 00:00 | |
| Look at U8 | 01/01/70 00:00 | |
| thank you | 01/01/70 00:00 | |
| KISS | 01/01/70 00:00 | |
| New problems ... | 01/01/70 00:00 | |
| picture | 01/01/70 00:00 | |
| Switches | 01/01/70 00:00 | |
| here you go sasha | 01/01/70 00:00 | |
| sry here .. | 01/01/70 00:00 | |
| Not clear | 01/01/70 00:00 | |
| if this is accurate, you are trying to r | 01/01/70 00:00 | |
| Looks ok | 01/01/70 00:00 | |
| the '244 output is connected NOT to a | 01/01/70 00:00 | |
| But wait, there's more | 01/01/70 00:00 | |
| So, how are they connected? | 01/01/70 00:00 | |
| New Questions | 01/01/70 00:00 | |
| 5.7V | 01/01/70 00:00 | |
| I have no recollection of asking about a | 01/01/70 00:00 | |
| Pull ups are definitely a good idea | 01/01/70 00:00 | |
| Look For... | 01/01/70 00:00 | |
| here .. | 01/01/70 00:00 | |
Ratings | 01/01/70 00:00 |