DIAGarI2C

[pancio]

Today I want to introduce my new tool which can communicate Atari with many I2C equipped devices. It's very simply interface contains special IC made by Philips in 90' PCF8584 connected directly to Atari bus. No all features works as expected at this moment but simple communication with e.g. PCF8574A(I/O expander) is possible and we can send and receive data. I wrote short library in MASM to communicate with PCF8584 but it still need some tweaks. Project will be available on my page with a few examples 🙂

I hope, someone will use Atari like Arduino 🙂

If anyone is interested to use/test/develop library I may send PCB :-)

DIAgarI2C-visualisation.png (497.99 KiB) 2403 mal betrachtet

BR,
pancio

[tfhh]

Today I want to introduce my new tool which can communicate Atari with many I2C equipped devices. It's very simply interface contains special IC made by Philips in 90' PCF8584 connected directly to Atari bus. No all features works as expected at this moment but simple communication with e.g. PCF8574A(I/O expander) is possible and we can send and receive data. I wrote short library in MASM to communicate with PCF8584 but it still need some tweaks. Project will be available on my page with a few examples

A very good idea! But, IMHO - it would be great to make V2 before this one really comes to market

Why? Having I2C directly controlled from the Atari is cool, but due to the passive integration you can only use it with assembly language.

My suggestion: Think about a PBI device with PBI handler ("I:" for example) and make it usable using some simple commands for every language like Basic or Turbo-Basic or whatever. THIS would be a really great thing, when hobbyist programmers can easily connect one or more I2C devices (temperature sensors, pressure detection, hundreds of more cool sensors, actuators and more).

The main problem of such expansions (see USB cartridge...) is the needed skills in assembly language. Most users won´t marry the machine, they want to have fun with fast success.

Just my 2 cents....

[pancio]

That's right! Assembler is not so hard to know but I can imagine the easier way like you mentioned :-)
The first thing I considered was checking if it was possible to connect anything containing I2C to an Atari without additional microcontrollers. Now I'm thinking about change idea...

It will be very helpfully if required code will be available from PBI ROM block. Of course it raising complex level, especially I've no experience with PBI/NewDevice features but I can also imagine device like ESP/ESP32 under Tasmota connected to Atari thru serial port which can communicate with any I2C device. I see good candidate which can be use: FujiNet :-)

What do you think?

BR,

[mega-hz]

PBI is - when once learned - pretty easy to solve.
There are some good Lessens on the CompyShop Magazin CSM and over the net documents too.
In this point the XL/XE OS is really future orientatetd to all kind of PBI Devices!
Even in 2024 (what noone of the developers would accepted those days!)
a good sample is the MSC Interface.
Just start playing around with the PBI,
first make 2 adress decoders (74x688 for D1XX and D8XX) and try to blend a 2K Rom into D8xx.
If you done that, the rest would be simple.

[Erhard]

Hi Pancio,

_IF_ you create a V2 device that includes PBI support then please add a controller to the board that supports communicating to one wire devices.

I once created a very simple Joystick port based interface that could do that and wrote the software in Action!

(I had 3 temperature sensors connected to the bus).

Unfortunately the required timing locks the computer. It cannot be done in vertical blanc because the "slow" one wire protol takes longer than one vertical blanc.

There is a "fast" one wire protocol but I didn't jump into that.

Erhard

[mega-hz]

i would suggest: PIpico!
extremly cheap and has much Power @133MHz with enough memory.
Esay to programm even with Arduino IDE.