| ??? 03/30/05 21:15 Read: times |
#90716 - Advanced Printing Responding to: ???'s previous message |
Ian Bell said:
The correct sequence is
1. Clock in the data 2. Latch the data 3. Strobe the print head 4. Move the motor Brian E. Cauchi said:
That's a classic sequence. But one thing I have never seen explained in a thermal line printer datasheet is that all these operations can be overlapped for a whopping print performance boost (CPU & printer permitting). I had thought of mentioning that during 3 & 4 you can clock in the next line of data but given the problems the OP was having getting any print I thought it best not to complicate matters. The main idea is to clock in the 'future' dot-line just after the latching and during the relatively long 'burn cycle' of the 'current' dot-line.
Also, the motor can be thought of as moving continuously, even though it really is driven in steps. In some of the systems we developed a dc motor was used to drive the printed medium so the moter was moving continuously. To play round with these things, the burn-time (i.e. the strobe pulse width) should ideally be regulated by hardware, for safety reasons. We used to include a one shot in series with the strobe port pin to ensure we did not keep blowing up heads until the SW guys got it right ;-) Just some ideas! As I am sure you know there are many more wrinkles to this thermal printing lark. I think we generated over 70 patents in the 10 years we spent developing label printers. So one piece of advice I would always give to anyone developing a commercial thermal printer product is check the patent postion. Ian |
| Topic | Author | Date |
| About developing thermal printing!! | 01/01/70 00:00 | |
| Guesses | 01/01/70 00:00 | |
| more guesses | 01/01/70 00:00 | |
| Oooh/. | 01/01/70 00:00 | |
| Thermal Printing | 01/01/70 00:00 | |
| Thanks for all your valuable experience! | 01/01/70 00:00 | |
| Does your paper advance? | 01/01/70 00:00 | |
| Yes | 01/01/70 00:00 | |
| short strobe? | 01/01/70 00:00 | |
| Some Answers | 01/01/70 00:00 | |
| Sorry, after testing, still have problem | 01/01/70 00:00 | |
| Print Sequence | 01/01/70 00:00 | |
| Thanks, i can print something now, but.. | 01/01/70 00:00 | |
| can print almost correct data now | 01/01/70 00:00 | |
| Print Sequence | 01/01/70 00:00 | |
| Advanced Printing | 01/01/70 00:00 | |
| Thermal printing larks... | 01/01/70 00:00 | |
Wrinkles | 01/01/70 00:00 | |
| circuit for the head | 01/01/70 00:00 | |
| The documentation of SMP610 | 01/01/70 00:00 |