Seeking input for my next "project."
Awhile back I bought the Sparkfun 4x20 LCD display (LCD-09568, https://www.sparkfun.com/products/9568 ) with a 1-wire interface good up to "38,400" baud . It was finicky and locked up frequently at 38,400 baud and at lower baud rates too. That problem is noted in several of the reviews. To SparkFun's credit, it offered to refund my whole cost. However, when I noticed it used the 18-pin PIC 16F88 chip that appears to be pin compatible to the 18-pin 16F1826/27 chips, with which I am familiar, and there are pads on the board for programming, I declined their kind offer. Only one pin of the MCU is not brought out to a pad on the board, RB5 pin 11. Also, note that the schematic available for a previous version of a SF serial display backpack "v28" is not the same as for the LCD-09568. I have attached a schematic that shows the pinouts and connections of the 16F88 as best I can determine:
(I didn't bother to trace out all of the resistors.)
My plan is to make it work with the PIC 16F88/16F1826/27 chips. My suspicion is that the code uses fixed delays rather than monitoring the "busy" signal.
Questions:
1) I would love to hear from others who have significant experience with that display.
2) Is 38,400 baud a reasonable target for that controller?
Finally, I have absolutely no financial motive in this and have told SparkFun that anything I develop will be open source. I paid full price plus shipping for the display I will be using for this project.
Regards, John
EDIT: Added "no" to my comment about financial motive. As I have said before and others here have witnessed, I am a horrible proofreader and have always had to rely on help from others for that.
Awhile back I bought the Sparkfun 4x20 LCD display (LCD-09568, https://www.sparkfun.com/products/9568 ) with a 1-wire interface good up to "38,400" baud . It was finicky and locked up frequently at 38,400 baud and at lower baud rates too. That problem is noted in several of the reviews. To SparkFun's credit, it offered to refund my whole cost. However, when I noticed it used the 18-pin PIC 16F88 chip that appears to be pin compatible to the 18-pin 16F1826/27 chips, with which I am familiar, and there are pads on the board for programming, I declined their kind offer. Only one pin of the MCU is not brought out to a pad on the board, RB5 pin 11. Also, note that the schematic available for a previous version of a SF serial display backpack "v28" is not the same as for the LCD-09568. I have attached a schematic that shows the pinouts and connections of the 16F88 as best I can determine:
(I didn't bother to trace out all of the resistors.)
My plan is to make it work with the PIC 16F88/16F1826/27 chips. My suspicion is that the code uses fixed delays rather than monitoring the "busy" signal.
Questions:
1) I would love to hear from others who have significant experience with that display.
2) Is 38,400 baud a reasonable target for that controller?
Finally, I have absolutely no financial motive in this and have told SparkFun that anything I develop will be open source. I paid full price plus shipping for the display I will be using for this project.
Regards, John
EDIT: Added "no" to my comment about financial motive. As I have said before and others here have witnessed, I am a horrible proofreader and have always had to rely on help from others for that.
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