EFX-TEK

TEK Talk => Hacking the HC-8+ => Topic started by: JonnyMac on May 14, 2016, 10:32:23 AM

Title: List of I2C Devices that Work with HC-8+ Programming/Boot Process
Post by: JonnyMac on May 14, 2016, 10:32:23 AM
The purpose of this thread is to provide a list (with demo code) of I2C displays/devices that allow the Propeller EEPROM to be programmed while the device is connected; when this is true the HC-8+ should boot from power-up as well.

As mentioned, not all I2C devices can operate at the speed the Propeller boot loader accesses the default EEPROM which can lead to problems during programming and power-up.

In general, if the display/device uses a known I2C chip versus a processor that allows for multi-mode communications, it should be fine.

All members are encouraged to contribute to this list in the form of demonstration code for a specific device. Please keep the general conversation vis-a-vis I2C in the other thread.
Title: PCF8574/PCF8574A LCD Module
Post by: JonnyMac on May 14, 2016, 10:38:26 AM
I have purchased these modules from Amazon many times; the trick is that they can use the PCF8574 or PCF8574A which have different slave IDs (both are general purpose IO chips). The LCD object allows for either device to be connected.

Example device:
-- http://www.amazon.com/Frentaly%C2%AE-Backlight-Arduino-MEGA2560-letters/dp/B0182N00LU

Thankfully, most vendors of PCF8574x backpacks are using the same circuit, so it's easy to find a display that will work with the attached code.
Title: MCP23008 LCD Backpack from Adafruit
Post by: JonnyMac on May 14, 2016, 10:42:20 AM
Like the PCF8574x, the MCP23008 is a general purpose IO device that works just fine on the Propeller EEPROM buss.

Example device:
-- https://www.adafruit.com/products/292

Note that while this is a multi-mode (I2C/SPI) device, it uses separate [native] chips for each process which allows I2C access compatible with the Propeller EEPROM buss.