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====== ECB-Cassette IF ======

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|\\ Home made alu bracket for the 3.5mm jacks.\\ \\ I made both for 300 baud and checked if they could “talk” correctly to each other. (as in backup/restore).\\ \\ Turns out I had to measure&select the timing capacitor C2 very precise to get 100% reliable interchangeable operation.\\ \\ I have now “upgraded one of the board to 600baud.\\ \\ I will modify the bracket to include the send/receive activity LEDs.\\ \\ Info: This pcb has ground plane on both side so no problem with the screws.|{{[[lib:plugins:ckgedit:fckeditor:userfiles:image:builderpages:speed3ple:images:img_20191015_174706small.jpg]] Cassette IF 300 and 600 baud}}                                                                                                   |
|Cassette IF in action in a backplane-4:                                                                                                                                                                                                                                                                                                                                                                                                                                                                    |{{[[lib:plugins:ckgedit:fckeditor:userfiles:image:builderpages:speed3ple:images:img_20200329_231926small.jpg]]
|\\ Cassette IF signal out on Scope:\\ \\ This is the “Kansas City” standard, one of several cassette formats in use at the time (mid 70's).\\ \\ Kasas City format use an continuous audio stream of a tone and shift that tone between 2400hz and 1200hz to indicate 1 or 0.\\ \\ 8 cycles of 2400hz represent a “1” bit or a MARK and\\ \\ 4 cycles of 1200hz represent a “0” bit or a SPACE.                                                                                                            |{{[[lib:plugins:ckgedit:fckeditor:userfiles:image:builderpages:speed3ple:images:img_20200329_230632small.jpg]]
|\\ Cassette Interface in use:\\ \\ To send a file to tape: **PIP PUN:=<filename.hex>[E]**\\ \\                                                                                                                                                                                                                                                                                                                                                                                                             |{{[[lib:plugins:ckgedit:fckeditor:userfiles:image:builderpages:speed3ple:images:img_20191013_011746small.jpg]]
|Cassette IF and technical document:                                                                                                                                                                                                                                                                                                                                                                                                                                                                        |{{[[lib:plugins:ckgedit:fckeditor:userfiles:image:builderpages:speed3ple:images:img_20200405_211813small.jpg]]
|Interconnecting 2 SBC and sending/receiving data through audio cable at 300baud:                                                                                                                                                                                                                                                                                                                                                                                                                           |                                                                                                                                                                                                                                                                                           |

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