| ??? 04/13/09 20:57 Read: times |
#164558 - No Responding to: ???'s previous message |
Richard Erlacher said:
but it can print, with proper software, in landscape. It's simple rotation ... BUT ... the entire bitmap normally has to be in memory. Additionally, pixel resolution may have to be modified, i.e. 15-16 pixel expansion, or the like.
There IS a problem, though. So long as it's unknown what the source format is, i.e. how many terabytes of source data per picodot, we can't even guess what's required. Until the necessary specifications are provided by the O/P, there's no benefit in wasting another bit of bandwidth on this issue. RE A n*90 degree rotation does not matter much, or hardly at all. The only graphical primitive that would care is bitmapped fonts. And the font bitmaps can be pre-rotated in flash. Bitmapped fonts are also the only graphic primitives that aren't scaleable, unless the free Hershey fonts are used. But the answer is still no: You do not have a need to store the entire bitmap in memory. You would need to store the full set of measurement values in memory, since the banding operation would require multiple passes throught the values. But it would be quite ok with a single byte for each horisontal pixel position. Because of resolution limitations with the selected printer, two tabulated variables would fit in 2*1500*1.5 = 4.5kB for landscape output and 3kB for portrait. And running a bitmap buffer for just a single head pass would take about 1kB. That comes to 5.5kB of RAM. Maybe 50-200 byte extra for computations and state information. Maybe the same for a communication buffer, and a quite normal stack for a non-recursive application. Any extra RAM would be a bonus, but not really required. And it is not a problem that we do not know everything about the source data. We do know the limitations of the output device. |
| Topic | Author | Date |
| How to print graphs on a printer at centronix port by 8051 | 01/01/70 00:00 | |
| Assume nothing! | 01/01/70 00:00 | |
| Specifications donot provide protocols | 01/01/70 00:00 | |
| So you need the technical specifications! | 01/01/70 00:00 | |
| Its a low cost Standalone system | 01/01/70 00:00 | |
| 01/01/70 00:00 | ||
| the protocol | 01/01/70 00:00 | |
| some links | 01/01/70 00:00 | |
| The signaling protocol is well-defined | 01/01/70 00:00 | |
| Actually quite simple to use a matrix printer. | 01/01/70 00:00 | |
| Questions of definition | 01/01/70 00:00 | |
| A graph normally requires graphics | 01/01/70 00:00 | |
| Indeed, but one is a subset of the other. | 01/01/70 00:00 | |
| You would do banded output | 01/01/70 00:00 | |
| suppose the data is presented in portrait format ... | 01/01/70 00:00 | |
| Band size doesn't matter so much | 01/01/70 00:00 | |
| It only feeds in portrait format | 01/01/70 00:00 | |
| No | 01/01/70 00:00 | |
You're right within the scope of your thinking | 01/01/70 00:00 |