Well, my LCD is back -- seems to be very twitchy about changing the address jumpers. Have to do with with all connections removed.
So long as you have the LCDs at different addresses you should be able to talk to them on the same buss. Again, I've done lots of I2C work and used many of the same devices on the same buss -- works.
I had these two LCDs working with Arduino before. i guess each LCD having their own pull ups is not the problem... They both have different addresses (0x20 and 0x27) and i don't understand why it is not working... Is there anything else I should try? For example, adding my own pull ups?
I'm wondering if wiring is part of the problem using the Propeller in open-drain mode. Perhaps inserting a PCA9515 between the Propeller and the LCDs would help buffer the signal.
I can order it and see. What would the Vcc be on this? Would i use another pin for En?
Worst case, i can use two more pins for another I2C bus and connect the second LCD to that which i already confirmed working... However this would defeat the purpose of having a bus (or buss as you would call )
The problem seems to occur when I change the jumpers while the board is still connected to the [powered-down] BoE. After disconnecting and letting it sit for a while, it comes back to life. Odd considering the simplicity of the circuit. I'm not going to bother Jameco -- would cost them and me more in time than the display is worth. I'm going to leave the jumpers as they are.
On an only-slightly related note... I picked up an OSEPP Arduino clone to try with the LCD as it has the same connector -- but the pin-out is different. Luckily, those connectors are easy to re-pin. I connected the LCD to the OSEPP Arduino and got it working -- so now I have it working for both processors.
I can order it and see. What would the Vcc be on this? Would i use another pin for En?
Figure 2 shows how to connect that device as a 3.3v to 5v translator. The EN pin is active-high so you can control it from the Propeller or just tie it to 3.3v.
JonnyMac: I will order this part today sice i have other things to order. However, since I can afford to use two extra pins in the remote controller for the boat, I will use the PCA9515 in the next revision of the circuit. I know it's going to sound stupid in this day and age but I am just not ready for SMD stuff yet. I use Fritzing to desing my circuits due to its simplicity; parts already exist for Adafruit, Sparkfun... etc. I use toner transfer method and THT parts (as much as possible). While Fritzing is capable of doing double side PCB, I have never done it before. It's next thing to do in my plans but i have to finish the boat project first... Again, thank you so much for your help. It would take much longer for me to figure this out. Sorry for your LCD troubles too
ltilghman: You are good with your LCD now, right? I am with mine...
In my May column I discuss my own move from through-hole to surface mount with a project I did for the QuickStart. Turned out my own worries were unfounded. I use DipTrace which has recently been updated to make ordering boards very easy (like ExpressPCB). And when you're happy, you have the ability to output Gerbers that you can send anywhere to be built. For example, I got 25 boards (from Gold Phoenix PCB) for my QuickStart project that were blue and done with a 3-day turnaround for $180 (that's cheap for the number of boards). I used 8 of those in this project:
As long as you have code space there's no reason you can't run two copies of the driver. Just define two objects and run the methods for each accordingly.
JonnyMac: I will order this part today sice i have other things to order. However, since I can afford to use two extra pins in the remote controller for the boat, I will use the PCA9515 in the next revision of the circuit. I know it's going to sound stupid in this day and age but I am just not ready for SMD stuff yet. I use Fritzing to desing my circuits due to its simplicity; parts already exist for Adafruit, Sparkfun... etc. I use toner transfer method and THT parts (as much as possible). While Fritzing is capable of doing double side PCB, I have never done it before. It's next thing to do in my plans but i have to finish the boat project first... Again, thank you so much for your help. It would take much longer for me to figure this out. Sorry for your LCD troubles too
ltilghman: You are good with your LCD now, right? I am with mine...
Comments
So long as you have the LCDs at different addresses you should be able to talk to them on the same buss. Again, I've done lots of I2C work and used many of the same devices on the same buss -- works.
http://www.mouser.com/ds/2/405/scps150b-115406.pdf
I can order it and see. What would the Vcc be on this? Would i use another pin for En?
Worst case, i can use two more pins for another I2C bus and connect the second LCD to that which i already confirmed working... However this would defeat the purpose of having a bus (or buss as you would call
I am really sorry that your having this kind of trouble.
I have had my LCD for quite sometime now and it has never had these problems.
Maybe you just got a lemon, will jameco replace it for you ?
On an only-slightly related note... I picked up an OSEPP Arduino clone to try with the LCD as it has the same connector -- but the pin-out is different. Luckily, those connectors are easy to re-pin. I connected the LCD to the OSEPP Arduino and got it working -- so now I have it working for both processors.
Figure 2 shows how to connect that device as a 3.3v to 5v translator. The EN pin is active-high so you can control it from the Propeller or just tie it to 3.3v.
You write a column ?
Where can it be found ?
Some past columns are available online here:
-- http://www.parallax.com/Resources/NutsVoltsColumns/TheSpinZone/tabid/781/Default.aspx
To save you some confusion, I prefer to use my stage name: Jon McPhalen. In fact, N&V now runs my column with that byline.
ltilghman: You are good with your LCD now, right? I am with mine...
As long as you have code space there's no reason you can't run two copies of the driver. Just define two objects and run the methods for each accordingly.
Seems so, yes.. Thanks for all the help.