mike_z

The response is 'NO DATA FOUND'. I know that there is a good leader tone. I can hear it on each recorder that I've used. My logic analyzer doesn't help with voltage levels, just timing. I can use a scope, but it is hard to sync on the changing signal. My GOOD reel to reel has plenty of volume. It can blow you out of the room. In fact with the volume up all the way, I have to turn off the speakers. Earlier in this thread someone gave a reference to the data stream characters. I was trying to see them, but the time of the bits was varying. That is why I thought that maybe the drive belt on the cassette was a problem. I suppose that I should try and find the characters using the reel to reel recorder. DO you know what bit pattern is used for the leader? I could easily see that, because it is repeating and last rather long. Mike

Well... here's what I did. Opened the 99 up and looked at 9901 pin 30 (think that is what it was) and connected my logic analyzer. I saw square waves that looked like data. I figured that maybe if I saved a simple program, just a bunch of A's, I might be able to see the A's in the data stream. Have not done that yet. I also pourchased a used 9901 on eBay and installed that, again no soap. Who knows if it was OK. I'm starting to run out of things to try, other than trying to see the A's in the data stream. Mike

Well.... today I received a new drive belt for my cassette. It made no difference. It will record, I can hear it, but will not read a recording. So, I dragged out my GOOD reel to reel tape recorder and I get the same results. There must be something wrong inside the 99. Mike

Lee.... thanks a million for the information. No, I'm not familiar with ALC. But I'm an old DEC and CPM guy. I know other assembly languages, so I believe I can understand this. There is also Google if I get stumped. I may have found a reason for my trouble. It may be recorder after all. Looking at the timing on the logic analyzer, the time of the zeros seems to vary. My sample rate on the Logic analyzer is 5 uSec, I would expect some difference but not more that 5-10 uSec. I'm seeing 50 uSec or more. This could screw up the bits. I'm going to check the belt in the recorder, it could have stretched and thus wobble the audio. The belt was changed a few years ago, but the recorder is not used a lot and could have kinked at the motor. I've seen this before. So, I suppose I should just replace the belt. If the sensing is 1.5 times the data rate, there should be plus or minus 362 uSec that the signal could vary before the bit could be read wrong. Did I read this correctly, the error would not be cumulative, because the timing starts at the flux change interrupt each time.? So, I'll see if I can improve the recorder and then check how that affects the data stream. Thanks again. Mike

I'm using a Realtone recorder, this is the same recorder that I used many years ago. I spent a lot of time cleaning it and it will record and play back well. My GE recorder does not output enough signal so I have abandoned using that one. I'm not sure I understand what "mains supply" is. Are you suggesting that I sub a power supply for the recorders batteries? The square wave signal I mentioned is at the 9901 chip on pin 30. This is the condition signal from the recorder. Using a scope I can see the frequency shift signals you mention on the output of the recorder. My logic analyzer captured a recorder signal from this pin 30 on the 9901 chip. This should be the digital signal the TI captures. BUT the leader, which the documentation says is 768 bytes of 00h is not that, but some thing else. It does look like it repeats I have to take some time to see what the bytes are and to see if I can find the DATA MARK. I saved a simple BASIC program 10 AAAAAAAA 20 BBBBBBBB 30 CCCCCCCC I hope to be able to find the 8 A's, 8 B's and 8 C's, I figure that they should be ASCII bytes. I don't know whether the LSB or the MSB are transmitted first or if there are any other bits included with the bytes. The documentation seems to indicate that there are no extra bits. Mike

I'm using an old mono Realtone cassette recorder. I tried a newer GE and the Audacity. I even amplified the signal some and still no soap. So I opened the unit up and looked at the signal going into the 9901 on pin 30. I get a nice square wave. I can not see the signal to well with the scope, but the leader looks like it might be OK. Maybe tomorrow I can drag out my logic analyzer and try can capture the wave form. Either the recording is not correct or there is something wrong with the 9901 or some other more inter parts. Thanks Mike

Well...... I believe that I see the rough format of a recording. I found what I think is a record. It starts with 8 bytes of 00 followed by one byte of FF followed by 64 bytes of data and then one byte for checksum. My recording is a short BASIC program. My question is what is the data format of the 64 bytes. Is it ASCII text? I would think that this maybe the case, how else could the program be listed? Is the data something else? Maybe tomorrow I can look a little closer and try and determine if the data is ASCII text. Thanks Mike

Thanks for the link. The cassette.htm is what I was looking for up the TI99 and see if I can capture the data at the TMS9901. Mike

Thanks I tried that, but to no avail. Does anyone know what the recording format is? What is the leader character? How many of them should there be? What is the data format. Is the data just straight? How is the memory addresses sent? Is there any checking CRC? Is there a trailer? Thanks Mike

Recently I came across my old TI99. I thought I'd try it and see if it would work. Seemed to have a few connection problems and the fuse let go on the power supply, but after a couple hours of cutting and soldering, it came to life. Then I tried writing a short basic program with the intention of saving it to cassette and then seeing if I could load it in again. I wrote three lines of basic, connect the cassette and typed SAVE CS1 After responding to the prompts, the program was saved. I listened to the tape and you can hear a leader and then the data burst. There is no trailer, is that correct? So Next I tried to load the program and it would not work. I turned off the TI99 so that there was nothing in it. Typed OLD CS1 started the cassette at the correct prompt. The tape recorder made the leader and data sounds, but the TI99 did not respond. After a while the TI99 responded NO DATA. After playing around with it a while I found that the DB9 I/O cord was bad. Replaced the DB9 connector and tried again, still no soap. I tried changing the volume (the only adjustment on the recorder) but still no data. Next I down loaded Audacity and tried that instead of my old cassette. Once again I could record the BASIC program but could not load it back to the TI99. Again I played with the volume etal but no soap, any ideas.? Thanks Mike

I picked up a bare board from J-data (thanks by the way) and intend to try it out sometime in the near future. My TI99 has suffered a port failure the 9901. I have removed the chip and am waiting for a replacement chip. I had intended to install a socket for the new chip. My question is, looking at some of the pictures of this F18A board, it appears that header pins come out over the 9901 chip. If I install a socket for the 9901 will that interfere with the F18A connection? Thanks Mike

Well..... I'm out of ideas on solving this problem. So I ordered a TMs9901 from ebay. Maybe a stab in the dark is worth the effort. Let you know, Mike

I made a bunch of recording, ranging from -18db to 0db. Then tried to use the tape decode program on all of them. The program reported that it successfully parsed the header and found 2 records, but sync failed on record 1a and all records were corrupt. So it appears that the volume needed for the tape decode program needs is not that important. Mike

Star, the Audacity recording has a low volume setting. At least the graphic it provides indicates no clipping. The Audacity program allows me to amplify the signal if necessary. Maybe the next test is to increase the volume a db or so at a time. Let you know, thanks for the help. Mike

This morning, I tried to load Python 2.7.18, this worked, but could not load PyAudio, kept getting a syntax error. So, I tried the same procedure on a different Windows 7 machine. For some reason, on this second machine, everything worked first try. Sometimes computers can really baffle me. Went back to the original Win7 machine and the same error........ Back to the TI99. I made a short 5 line basic program and tried to save it using my Audacity program. Made three copies and transferred them to the 2nd Win7 machine. Loaded up the files and tried the tape decode program. It worked was the good news, the bad news is that the recording is bad. This is the response of the tape decode program 607415: Training COmplete, symbol len. = 31.9875 791876: Successfully parsed header: rec count = 1 810812: WARNING: record 1a incorrect checksum 830162: WARNING: record 1b incorrect checksum 830162: ERROR: Record 1 both primary and secondary records corrupted 830162: ERROR: data received bu corrupt 830162: -------------------------------- The second recording was similar, but included a syncronization error. Another recording with more records had all four records bad. Then the last recording reported Header record count mismatch. This seems to imply that the records, without regard to the method (cassette or Audacity) results in a bad recording. This is in line with the inability of reading them. Can I believe this? I'd like to have a wave file recording that I know works. Can anyone make a short TI99 wave file recording using Audacity and email it to me. I'd like to try a known good recording on the tape decode program. In every run of the tape decode program, using my recording, it only reported errors and never made a TAPE_xxx.dat file. I appreciate your efforts, thanks, Mike

Just for grins, I downloaded 2.7.10 and 2.7.18 and tried them. Get the same syntax error when I try and install the module pyaudio. Rats.

I downloaded Python 2.7.12 and the pyaudio for cp27. I could get Python loaded and could run it, but for some reason I could not load the module pyaudio. I uninstalled both 2.7 and 3.8 and started over, but I've been struggling all afternoon getting Python 2.7 installed with pyaudio. Time to give up for today, Mike

Star, this code was posted on GitHub 4 years ago, so maybe it is Python2. I'm aware that Python 2 and Python3 are not the same and 3 may not run 2. I wonder if I need to try and run this code with Python2. Thanks for the help, Mike.

Here is the area where the error occurs. Line 754 parser.add_argument( '--profile', dest="profile", default=DEFAULT_PROFILE, choices=profiles.keys().append('?'), <-- line 754 metavar='P', help="Use given decoder configuration profile. Use '?' to get " "a list of available profiles. Default: " + DEFAULT_PROFILE) Python is complaining about the append. Stating that keys() doesn't have an attribute called append. Mike I also see that keys() is only mentioned twice in the code. Line 754 and 778.

Star, this morning I downloaded python 3.8.8. This is not the newest version, but the latest version of python that will run on WIN7. I downloaded the TI99 decode file and tried to run it. An error occurred saying I need PyAudio. It took a while to figure out which PyAudio I needed. pyaudio-0.2.11-cp38-cp38-win-amd64.whl. The cp refers to the python version. I downloaded a few others prior to learning this and received plenty of errors. Eventually I got pyaudio installed and python would run. I tried the program ti99_4a_tape_decode.py first.wav ---- this resulted in another error that appears to be a program attribute error. There is no append attribute to some program object. Seems there are a lot of road blocks here. I don't know python that well to understand this. I'll take some time to look at it, it says it is at line 754. Mike

You know, I saw that Python program on GitHub, but am unsure of how to use it. I've used Python on an Arduino and Raspberry PI. DO I need Python on my PC to run the program? Have you tried this software? Mike

I wonder if it could be just low signal level. What I just did was to monitor the INT REQ on the 9011. It is an active low. I see 4+ volts while the TI99 is idle. Then when I read a tape, once the sound starts I see low pulses. After the recording ends, the interrupt requests continue, as if the READ program is looking for more. Kinda hints at bad checksums? Mike

Star, I did some experimentation with the recorders volume and watching pin 28 on the 9901. If the volume is too low, the pulses are miss formed. I need to have my recorder volume at 9 - 10 to obtain nice square waves. Somehow the OS must grab the recorder data from the 9901 and incorporate it into the video signal. This seems to work. The OS also has to grab the data, and information in the header in order to store the data in memory. Since I think the data is coming out of the 9901, either there is a part failure or the data stream is faulty. The CHECK program does not place anything in memory, it just compares what is received with what already is in memory. Whereas the READ program deposits what comes in, into memory. Therefore I'm still thinking that either the data is corrupt or the CPU is fumbling. Somewhere I saw some documentation regarding the recording data stream. Maybe I can verify that my recording is correct. Mike

I do not know. Never had a joystick. Mike

I cranked up the volume on the Audacity wave file. I can hear the wave file sound on the monitor. Not as loud as the tape recorder. I see that there is a 15 ohm resistor across the input, quite a load, maybe my PC can not drive that very well? The fact that the recording sound can be heard on the monitor kinda tells me that the recording is getting through the 9901, but somehow does not make it to memory. I have to dig some more. Star, No I do not have minimemory or easybug. I'll look into those, but again I'm wondering if the 9901 is good or not. THanks Mike