| ??? 08/27/05 14:29 Read: times |
#100178 - Memory mapped LCD problems Responding to: ???'s previous message |
Everything appears to be working fine on my 8052.com SBC except for Memory mapped LCD. I set it up with the M0I command and the display seems to initialize, that is, completely blank but no cursor as in Direct mode. Using the LCD write test command leaves the LCD blank. Loading the Clock demo program usually also leaves the LCD blank although sometimes it results in streaming random characters running on the LCD. While the clock program is running I scoped P0 lines and saw extremely long rise times on all P0 pins, in the order of 20-30 microseconds. All pins but power show swithing signals. Running the keypad demo program the P0 lines have very sharp risetimes. This makes me think that possibly the LCD is going into Read mode where we have the LCD and the MCU trying to drive P0.
Trying to determine the source for the R/S and R/W signals but the resolution on the GIF images for the schematics is too low and I cannot read most of the signal names. Anyone else having this problem? By the way, the LCD works perfect connected to the Direct Connect. Hal |
| Topic | Author | Date |
| 8052.com SBC | 01/01/70 00:00 | |
| SBC | 01/01/70 00:00 | |
| I'm Interested, but no big hurry | 01/01/70 00:00 | |
| Good point | 01/01/70 00:00 | |
| BTW | 01/01/70 00:00 | |
| I'll update | 01/01/70 00:00 | |
| This is a nice chip when you need pins g | 01/01/70 00:00 | |
| Questioins | 01/01/70 00:00 | |
| elaborations | 01/01/70 00:00 | |
| RD2 programming | 01/01/70 00:00 | |
| Question | 01/01/70 00:00 | |
| RD2 and PSEN | 01/01/70 00:00 | |
| LeDot | 01/01/70 00:00 | |
| solder point | 01/01/70 00:00 | |
| go figure | 01/01/70 00:00 | |
| solder point/LeDot | 01/01/70 00:00 | |
| Jumper/button | 01/01/70 00:00 | |
| datasheet | 01/01/70 00:00 | |
| RD2, /PSEN and the joy of being perfect | 01/01/70 00:00 | |
| I think | 01/01/70 00:00 | |
| Herr Ohm says no | 01/01/70 00:00 | |
| Hands off | 01/01/70 00:00 | |
| no touch | 01/01/70 00:00 | |
| tidbits | 01/01/70 00:00 | |
| AT89S8253 | 01/01/70 00:00 | |
| First hand experiance | 01/01/70 00:00 | |
| RE:Experience | 01/01/70 00:00 | |
| SBC page updated | 01/01/70 00:00 | |
| Required HW for 8052.com Institute of uC | 01/01/70 00:00 | |
| that Erik has voluteered to teach ??? | 01/01/70 00:00 | |
| Retirement | 01/01/70 00:00 | |
| Well | 01/01/70 00:00 | |
| genetically as well | 01/01/70 00:00 | |
| I too... | 01/01/70 00:00 | |
| u51 one possibility | 01/01/70 00:00 | |
| I like part of that | 01/01/70 00:00 | |
| not good | 01/01/70 00:00 | |
| I see your point - did you see mine? | 01/01/70 00:00 | |
| got better | 01/01/70 00:00 | |
| you did not | 01/01/70 00:00 | |
| Are you sure about your .29$ | 01/01/70 00:00 | |
| oops | 01/01/70 00:00 | |
| single nand gate?? | 01/01/70 00:00 | |
| Ok spelling it out | 01/01/70 00:00 | |
| And it supports DS89C4x0! | 01/01/70 00:00 | |
| Nice effort | 01/01/70 00:00 | |
| PCB layouts | 01/01/70 00:00 | |
| not even gerber? | 01/01/70 00:00 | |
| ExpressPCB | 01/01/70 00:00 | |
| Keil was | 01/01/70 00:00 | |
| If needs be | 01/01/70 00:00 | |
| 8052.com SBC available for ordering | 01/01/70 00:00 | |
| Selling like hotcakes? | 01/01/70 00:00 | |
| Not bad | 01/01/70 00:00 | |
| AT89S8253 | 01/01/70 00:00 | |
| Yes | 01/01/70 00:00 | |
| Errata | 01/01/70 00:00 | |
| AT89S8253 ISP | 01/01/70 00:00 | |
| Didn't look very hard | 01/01/70 00:00 | |
| I already tried | 01/01/70 00:00 | |
| 8052.com SBC and 8052Sim | 01/01/70 00:00 | |
| Sort of and yes | 01/01/70 00:00 | |
| Pinnacle52 | 01/01/70 00:00 | |
| Why? | 01/01/70 00:00 | |
| Touche' | 01/01/70 00:00 | |
| Hard to resist | 01/01/70 00:00 | |
| Dress | 01/01/70 00:00 | |
| re classes etc | 01/01/70 00:00 | |
| re classes etc - an example | 01/01/70 00:00 | |
| Question on BOM | 01/01/70 00:00 | |
| Yes | 01/01/70 00:00 | |
| New Items added to 8052.com SBC Page | 01/01/70 00:00 | |
| 74LS573? | 01/01/70 00:00 | |
| Correct | 01/01/70 00:00 | |
| reset | 01/01/70 00:00 | |
| Errata | 01/01/70 00:00 | |
| Mine has arrived . . . | 01/01/70 00:00 | |
| Wow | 01/01/70 00:00 | |
| A minor problem | 01/01/70 00:00 | |
| Caps for MAX232 | 01/01/70 00:00 | |
| Whole point.... | 01/01/70 00:00 | |
| MAX232 Caps | 01/01/70 00:00 | |
| Deflux | 01/01/70 00:00 | |
| Works like a charm! | 01/01/70 00:00 | |
| Never mind, got it figured out | 01/01/70 00:00 | |
| Glad you got it working | 01/01/70 00:00 | |
| SBC-BASIC | 01/01/70 00:00 | |
| See email | 01/01/70 00:00 | |
| yes I will... | 01/01/70 00:00 | |
| Any luck with that yet? | 01/01/70 00:00 | |
| Not yet | 01/01/70 00:00 | |
| Sure! | 01/01/70 00:00 | |
| in that case... | 01/01/70 00:00 | |
| I've got a couple of RD2's | 01/01/70 00:00 | |
| http://www.efton.sk | 01/01/70 00:00 | |
| What about ED2's | 01/01/70 00:00 | |
| yes | 01/01/70 00:00 | |
| Basic 52/RD2 | 01/01/70 00:00 | |
| b52rd2 | 01/01/70 00:00 | |
| it works for me | 01/01/70 00:00 | |
| Real hackers | 01/01/70 00:00 | |
Basic 52 | 01/01/70 00:00 | |
| I got mine today! | 01/01/70 00:00 | |
| Darn the luck | 01/01/70 00:00 | |
| Comments | 01/01/70 00:00 | |
| Our Radio Shack Stinks | 01/01/70 00:00 | |
| An Idea | 01/01/70 00:00 | |
| 125 | 01/01/70 00:00 | |
| RE: '125 and JP4 | 01/01/70 00:00 | |
| Yes position? | 01/01/70 00:00 | |
| Got it - Bad 8253 | 01/01/70 00:00 | |
| No explanation | 01/01/70 00:00 | |
| You were right the first time - my bad | 01/01/70 00:00 | |
| No problem | 01/01/70 00:00 | |
| Memory mapped LCD problems | 01/01/70 00:00 | |
| Hmmm | 01/01/70 00:00 | |
| Building one | 01/01/70 00:00 | |
| Microseconds? | 01/01/70 00:00 | |
| Scale error | 01/01/70 00:00 | |
| Memory-mapped LCD initialization | 01/01/70 00:00 | |
| Thanks, Craig! It works! | 01/01/70 00:00 | |
| SBC - Manual | 01/01/70 00:00 | |
| SBC document | 01/01/70 00:00 |