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TI 99/4A interfacing

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For the lack of a working printer with serial or parallel port, I've used my 99/4A connected serially with a small laptop, which acts as a print server. It reads the incoming text on the serial port (in reality a USB - RS232 converter) and prints it on a networked laser printer. So for sure you can communicate serially between different computers.

 

For a game application, I'd recommend setting one of the computers up as a server, the other as a client. With regular intervals, the client writes a pre-determined block of data to the server, which responds by returning a similar block to the client. That's the most efficient transfer mode.

If you don't need block transfer, instead set up a short message to be sent with regular intervals from the client to the server. The server will respond with a similar message. The message is coded with a data identifier and some data. By sending data at regular intervals you make the transfer deterministic, which is good in real-time games.

Then you queue up data you want to transfer. Say you have two players in a game, each played on one computer. The only action you can do is throwing a bomb to a certain location.

When no bomb is thrown, you repeatedly send PXxxxx or PYyyyy, to tell the other computer where your player is. If you throw a bomb, the messages BXxxxx and BYyyyy are queued. They will be sent by next two messages, and then the communication routine returns to sending player positions again.

Also add a message ID, like a digit from 0 to 9, incremented at each transfer. The same digit is returned by the other computer each time. This way, both will know that new messages are coming from the other computer, and that they are received and returned. If you feel it's critical, add a checksum to make sure each message is valid. But it doesn't matter in a game application.

If you hit the player you may get DXxxxx and DYyyyy back, to tell that he's dead at a certain position. You can easily define messages like Status Restart, Status Lost, Status Stealth or whatever is applicable to your game.

 

This message structure is similar to what is used in CAN networks in cars. By keeping the transfer routing ticking by itself, eating data from the queue, you can easily separate the tasks of communication and handling the data to send. You need to write som interrupt-driven communication, of course, but that's doable. Ten messages per second serially shouldn't be impossible, and that's pretty good for a game played by a person, if you keep the data simple.

 

As you can perhaps understand I've implemented exactly this, but in a different context than gaming on a 99/4A.

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Here's a new blog entry http://atariage.com/forums/blog/659/entry-13589-parallel-port-interfacing-using-extended-basic-on-the-ti-994a-computer/ detailing how to interface the TI 99/4A computer using the parallel port from within Extended Basic. This is primarily targeted at rapid prototyping as well as for users who do not have knowledge of assembly language.

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Here's a new blog entry http://atariage.com/forums/blog/659/entry-13589-parallel-port-interfacing-using-extended-basic-on-the-ti-994a-computer/ detailing how to interface the TI 99/4A computer using the parallel port from within Extended Basic. This is primarily targeted at rapid prototyping as well as for users who do not have knowledge of assembly language.

 

Already been there! Nice entry!

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I really have not actually, with the exception of having a PEB cable extension. Otherwise, the changes have been internal with an ATX power supply and an HRD replacing my flaky IDE card. I'm filming from a different angle this time though :) Speaking of filming, I think it's high time to replace my video camera. The one I'm using currently is the Sony DCR-TRV22. Used to be higher end maybe 15 years ago when I bought it new, but the footage is too grainy for today's standards and it doesn't perform well under fluorescent lighting which is what I have in my hobby room.

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Here's a quick demo of wireless communication between the TI and an Arduino using 2 XBee modules. This is a proof of concept test relating to my wireless weather station project. You can read about it here: http://atariage.com/forums/blog/659/entry-13546-wireless-weather-station-managed-by-the-ti-994a-last-update-13117/

 

https://youtu.be/-9D0889Mks0

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That video is too cool, Vorticon. :)

 

 

I have been contemplating finding cool ways to use the serial port, once I get all the other things lined out with my system. I want to make an AV switch to swap the input for my game systems on my CRT. This would be opening Telco, sending data to an Arduino Uno and using the powered outputs on the Arduino to select a position on a homemade 4 way switch I've sketched out (breadboard).

 

The arduino scripting language is basically just C++, so pretty high level stuff... Should be fun as a project with the boy.

 

Your projects are very inspiring. :D

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Tursi, are the A/D pins on the ubergrom input only or bidirectional?

A/D is by definition one-way (analog to digital - input only).

 

But there are also 6 digital GPIO pins that can be configured as input or output.

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Connecting two Consoles.

I was pondering on my Thread on Joystick Port Interfacing how I might transfer a couple of variables (or more) between two 99 consoles and wondered if the following would work?

By inter-connecting the Cassette Mic. and Ear sockets between two consoles and driving a Joystick key input with the Cassette Motor Drive output then it should be possible to PRINT and INPUT between units on a Keyboard 3 branch.

Has anyone tried this or would like to?
Any other ideas? Console and BASIC only!
To find out why I was thinking this then you would have to look at the other Post here:

 

 

http://atariage.com/forums/topic/262077-joystick-port-interfacing-ti-basic-console-only/

Edited by Meddler

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I love any kind of interfacing. :)

 

This could be a primitive precursor to a 2 player gaming format... Chess or something of the like.

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And he is using RXB subprogram command CALL IO to do all of this!

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Hi, butting in to say that I have received this nasty little thing, "cheap-as-chips" from China.

post-45502-0-90126400-1490273414_thumb.pngAbsolutely no information....MP3, Bluetooth, USB,FM Radio etc.

The idea being that it replaces the Cassette Player. It might do more as it is a USB host.

Hopefully, it will be straight forward but if anyone recognizes the chip: AC1652DAK115-0 marked JL then that would help.

http://www.ebay.co.uk/itm/262711322166

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Well this kinda helps if you speak what ever he is saying????

 

 

Or better is:

 

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Hi, butting in to say that I have received this nasty little thing, "cheap-as-chips" from China.

attachicon.gifs-b275x275.PNGAbsolutely no information....MP3, Bluetooth, USB,FM Radio etc.

The idea being that it replaces the Cassette Player. It might do more as it is a USB host.

Hopefully, it will be straight forward but if anyone recognizes the chip: AC1652DAK115-0 marked JL then that would help.

http://www.ebay.co.uk/itm/262711322166

Well that did not work out so well....

but could this be the answer? Record to SD card and scrolling display; edit on P.C if necessary

post-45502-0-47906200-1491737488_thumb.jpg

* It saves all data in SD card

* High quality recording, listen recording files clearly

* Support recorded files and MP3 songs playback

* Manage in real time

* Quickly and Easily searching conversation call with pressing button

* Manual controls: Pause, Continue play

* 1GB Memory size can record 35 hours

* Start Recording time sensitivity

* Each call has data and time in detail to assist searching

* Allows to change recording volume

 

http://www.ebay.co.uk/itm/322204331089

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Here's the latest update video on the wireless weather station project.

The analog temp sensor has been replaced with a digital one and the wind and rain sensors are now online. This essentially completes the technical development of the project and now it's just a matter of creating an appropriate enclosure and refining the RXB interface. More details here: http://atariage.com/forums/blog/659/entry-13546-wireless-weather-station-managed-by-the-ti-994a-last-update-42617/

 

https://youtu.be/51o0DZ_8CwE

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