Fun with Harprit's book...
rohorn
Posts: 2
New at all this and have a need to learn it - so I got Harprit's book a few months ago at the local bookstore. It is even more educational now that I have the hardware!
Spent the last few evenings trying to get the display working with the "LCDminimal" program in Ch.14. All I got was 1 row of faint black squares. I was wondering if the display was bad, so I tried a display demo from the Object Exchange - now I have TWO rows of solid black squares - and faint readouts if the LCD is held at funny angles! Turns out that the contrast pin didn't like being grounded after all - replaced the jumper with a 2K resistor and it worked perfectly. But at least I got to see how the Object Exchange works - and how OBJ works in Prop Tool - that was neat!
Went back to "LCDminimal", compared it to the LCD data sheet, learned a lot, accomplished nothing, wondered why the display demo readout would still be on the display even though "LCDminimal" was uploaded, which didn't make sense. Checked the schematic against the program - and there it was - the "enable" and "write" display pins are assigned the wrong pins in the program (or the schematic is wrong).
And that has resulted in a good evening - I learned something, got results, and nothing caught fire. I'm looking forwards to finishing this book with more of that.
Spent the last few evenings trying to get the display working with the "LCDminimal" program in Ch.14. All I got was 1 row of faint black squares. I was wondering if the display was bad, so I tried a display demo from the Object Exchange - now I have TWO rows of solid black squares - and faint readouts if the LCD is held at funny angles! Turns out that the contrast pin didn't like being grounded after all - replaced the jumper with a 2K resistor and it worked perfectly. But at least I got to see how the Object Exchange works - and how OBJ works in Prop Tool - that was neat!
Went back to "LCDminimal", compared it to the LCD data sheet, learned a lot, accomplished nothing, wondered why the display demo readout would still be on the display even though "LCDminimal" was uploaded, which didn't make sense. Checked the schematic against the program - and there it was - the "enable" and "write" display pins are assigned the wrong pins in the program (or the schematic is wrong).
And that has resulted in a good evening - I learned something, got results, and nothing caught fire. I'm looking forwards to finishing this book with more of that.
1601 x 1200 - 339K
Comments
Programming & Customizing the Multicore Propeller Microcontroller: Official Guide is a much better book.
John Abshier
Cool Beans!
Are you using this book along with or instead of the regular propeller manual?