[Coco] Trying to understand reading Cassette BASIC

[Luis Fernández]

Not understand, because compared, only the last half of the waveform, with the time value for the entire waveform
Explication:
In A7AD RESET PERIOD TIMER
WAIT UNTIL CASSETTE GOES LO (Only half Wave)
and compared with the throughout the full waveform     (ERROR)

1100 A7AD 0F 83              LA7AD CLR CPERTM            RESET PERIOD TIMER
1101 A7AF 8D C6                         BSR LA777                WAIT UNTIL CASSETTE GOES LO
1102 A7B1 D6 83              LA7B1 LDB CPERTM            GET PERIOD TIMER
1103 A7B3 D1 90                         CMPB CMP0             UPPER LIMIT OF 1200 HZ PERIOD
1104 A7B5 22 03                         BHI LA7BA                 BRANCH IF CASSETTE SPEED IS TOO SLOW OR DROPOUT
1105 A7B7 D1 91                         CMPB CMP1             UPPER LIMIT OF 2400 HZ PERIOD
1106 A7B9 39                               RTS
1107 A7BA 0F 82              LA7BA CLR CPULWD            RESET UP TO SPEED COUNTER
1108 A7BC 39                              RTS


Mr. Robert Gauld Can you help?

for me the result is almost always going to be very short, or 2400 or more

of course, I have some error because the routine works, but can not find where that wrong



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Excuse my English, I use google translator, my language is Spanish, I'm Spanish but I live in Venezuela
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