So I found this old chip in a very old piece of technology from my local college. It was mounted on the board with a socket but unfortunately I couldn't get that.
I've done some research but just by looking at it you can tell it has a BASIC interpreter and debugger inside of it. What I want to know, is how I would interface with this and perhaps program it in BASIC. Maybe some of the more knowledgeable can help me with this one, but I would love to have a tiny BASIC computer that I can program with maybe a 16x2 character lcd (which would mean I'd have to bring an arduino into play but that's ok as long as it's just for the screen.)

I found this article that says I can program it just by hooking up a terminal to it...? What does that mean?

EDIT: I found a post on GitHub about someone who has figured out how to interface with this chip and it involves this adafruit product, except I can't find a good datasheet on this chip and the picture on GitHub fails to show me the actual wires and where they go.

PICTURE:
I have used the power of logic to figure out the pins to the following image based on the small amount of wire we can see:

Gnd is obviously Gnd
VCC is obviously VCC
TX seems to be orange and the only orange wire not going to the VCC pin is pin 5
RX must be the white wire because we can't see it coming out. it goes to pin 6

Can someone please verify my reasoning/recognizing this image? Thanks!

And, if the only signals going to it are RX and TX couldn't I just use an arduino with the atmega removed?
With a little bit of googling I found the datasheet for that chip and its reference manual, which I've mirrored to the Internet Archive for reliable reference in the future.



Pin assignments are on the first page of the datasheet, which is pretty easy to read; ask if you want clarification on anything in there.


I also found somebody's notes on the chip (in German) with some neat links, including mention of an emulator that no longer seems to be online. Sad
I did find that german site and indeed there was no emulator Sad
Thanks for posting that image, it is very helpful but also confusing if you look at the pin assignments and the image above on github. Pins 5 and 6 are P30 and RESET which makes no sense with the TX and RX connections to the adafruit device... so I am again questioning the connections to the chip.
Trust the datasheet. Trying to figure things out from an incidental photo is a good way to be wrong.
I would use the datasheet if I knew the equivalents of RX and TX using the given pin assignments.
The manuals are pretty shy about saying exactly how you're supposed to interactively communicate with the system, yeah. Section 7-1 of the reference manual states it configures itself for communication with a teleprinter (so it's a serial terminal), and page 7 of the datasheet says P30 and P37 are the serial lines, apparently configured for 8n2 by default with an unspecified bit rate.
According to the github page the baudrate is set by pulling down 3 of the pins which you can see in the picture. That's good if it's serial lines, does that mean I can use an arduino as a serial terminal?

EDIT:: It's not down, you pull them up to set the baudrate.
Oh, cute- it reads the desired bitrate (assuming an 8 MHz system clock I think?) from 0xFFFD in memory, so you could force a particular one even without a ROM by putting pull-up/down resistors on the 3 LSbs of the data bus. See page B-1 of the reference manual.

I don't think it's possible to use an arduino as a serial terminal on its own, since while they do (some of them?) have a USB-UART bridge onboard, it's not exposed somewhere easy to connect to.

Consider Sparkfun's guide to connecting to a serial device.
I have no doubt now that I know the serial pins on the chip that I can use the adafruit device above but that Sparkfun site did learn me some terms I hadn't known before. I just don't want to buy the adafruit FTDI device until I know for sure the arduino can't be used. The UNO I know can be used as a serial terminal by removing the ATMEGA chip and hooking up RX to the RX pin on the uno and same with the TX and then just 5V and ground. I do this whenever programming my homemade calculator. I just wonder if this chip does the same thing.
Botboy3000 wrote:
The UNO I know can be used as a serial terminal by removing the ATMEGA chip and hooking up RX to the RX pin on the uno and same with the TX and then just 5V and ground. I do this whenever programming my homemade calculator. I just wonder if this chip does the same thing.
Yeah, that should work in the same way with this chip.
Alright, and the final piece of the puzzle is just an 8MHz clock and a couple capacitors which I currently don't have... as far as I know. I could check my parts box. There might be one in there. but I think that's a project for tomorrow as today is a very busy day. Getting excited, but cautiously.

EDIT:: So... I'm a total moron.
the github page actually had it's own lables for the pins if I had just scrolled up a bit...

Code:
Z8671   
---------   
VCC   P36       
X2    P31         
X1    P27     
TX    P26       
RX    P25         
/RES  P24       
R/W   P23       
/DS   P22       
/AS   P21       
P35   P20       
GND   P33         
P32   P34         
A8     d7       
A9     d6       
A10    d5       
A11    d4           
A12    d3       
A13    d2           
A14    d1           
A15    d0
  
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