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31 lines
661 B
Plaintext
31 lines
661 B
Plaintext
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%import textio
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main {
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sub crc16(uword data, uword length) -> uword {
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uword crc = 0
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repeat length {
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crc ^= @(data) << $0008
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repeat 8 {
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if crc & $8000
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crc = (crc<<1)^$1021
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else
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crc<<=1
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}
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data++
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}
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return crc
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}
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sub start() {
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txt.print("calculating...")
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c64.SETTIM(0,0,0)
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uword crc = crc16($e000, $2000)
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txt.print_uwhex(crc, true) ; should be $ffd0
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txt.nl()
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txt.print_uw(c64.RDTIM16())
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txt.print(" jiffies")
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sys.wait(100)
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}
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}
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