Cassette Support

Real Cassette

For details on how to use a real cassette player connected to a PC and Emma 02 please see the chapter: Real Cassette Support

Wave Files

The easiest and fastest way to load or save a .wav file into the ETI 660 emulator is by making sure both options 'Turbo LOAD/SAVE' and 'Auto LOAD/SAVE' are checked, this should be the default setting when the Emma 02 emulator is started for the first time. Depending on which type you choose, i.e. automatic or manual please follow the instructions below.

Note that we have not been able to load any of the saved wav files on a real ETI 660. If you have/need that option, please let me know and we can do some trouble shooting on this. Changing the wave file settings might impact the usability of the wav files on a real ETI 660, see also below.

Auto LOAD/SAVE

Default settings, to use this make sure 'Auto LOAD/SAVE' is checked.

To load a .wav file into the ETI 660, start the Emma 02 emulator and then the ETI 660 emulator (start button on ETI 660 tab). Select a .wav file in the Emma 02 window by selecting the 'Cassette' button. Then press '4' on the ETI 660 emulator window and the cassette PLAY button should go green.

To save a .wav file from the ETI 660, Select a .wav file in the Emma 02 window by selecting the 'Cassette' button. Press '2' on the ETI 660 emulator window and the cassette REC button should go red.

For both save and load make sure a .wav file is selected in the Emma 02 window before using the save and load instructions otherwise the ETI 660 emulator will hang on the load (until you manually start a .wav file) or with a save the wav sound will not be written to any file.

The emulator will attempt to fill the start and end address of the software on memory location hex 400-403. The following locations will be used:

LOAD
Start: 600
End: last byte loaded

SAVE
Start: 600
End: highest address that was used in any memory write instruction since starting ETI 660 emulator

Note that after loading SW the emulator will perform an automatic reset to get the screen enabled.

Manual LOAD/SAVE

To use this make sure 'Auto LOAD/SAVE' is NOT checked. This setting is more like the cassette handling is on the real ETI 660 however more complicated than Auto LOAD/SAVE.

Before starting to load or save make sure 400/401 contains the start address and 402/403 the end address.

To load a .wav file into the ETI 660, start the Emma 02 emulator and then the ETI 660 emulator (start button on ETI 660 tab). Select a .wav file in the Emma 02 window by selecting the 'Cassette' button. Press play and after that as soon as possible press '4' on the ETI 660.

To save a .wav file from the ETI 660, Select a .wav file in the Emma 02 window by selecting the 'Cassette' button after that Press the dark red recording button and Press '2' on the ETI 660.

Turbo LOAD/SAVE

When Turbo LOAD/SAVE is selected the emulator will increase speed when a wav file is played to allow faster LOAD and SAVE possibility in the emulator. The speed of the Turbo LOAD/SAVE can be changed; default is 15 MHz, which works ok on both my desktop and laptop. Too high values will not run ok on slower PCs as all CPU power will be used by the emulator. On my vista desktop vista limits CPU usage to 50% max but on my windows 2000 laptop CPU usage gets up to 100% and can possibly hang the laptop for the duration of the LOAD or SAVE command.

Wave File Settings

Via the 'Settings' drop down menu select 'Wav File and Real Cassette Settings' to change the wave file settings used for saving or loading a '.wav' file. . The following subchapters describe applicable settings in more detail. Settings for saving to a file are the 'Wave volume', 'Bit Rate' and 'Bits per sample', setting for loading a wav file are the 'Wav file conversion' and 'Reversed Polarity'. The 'Cassette conversion' and 'Input Channel' are only used for Real Cassette loading.

Wave volume

1 to 15 (where 15 is the loudest)

Bit Rate

11025, 22050, 44100 or 88200 (samples per second)

Bits per sample

8 or 16

Wav file conversion

Two conversion types can be used:
1. Amplitude: where the signal is converted to a 1 on positive amplitude and a 0 on a negative amplitude.
2. Sinus: where the signal is converted to a 1 on an upward sinus and a 0 on a downward sinus

Default this is set to 'Amplitude' which works for all my wav files. Depending on the emulated computer this might need to be changed if loading does not work or gives tape errors.

Reversed Polarity

Switch converted signal polarity (1->0 and 0->1) as described for conversion types above.