Chapter 11 Serial Interface 0, 1

„Tranfer Bit Count and First Transfer Bit

When the transfer bit is 1 bit to 7 bits, the data storing method to the transmission data buffer TXBUFn is different, depending on the first transfer bit selection. At MSB first, use the upper bits of TXBUFn for storing. When there are 6 bits to be transfered, as shown on figure 11-3-1, if data "A" to "F" are stored to bp2 to bp7 of TXBUFn, the transmission is operated from "F" to "A". At LSB first, use the lower bits of TXBUFn for storing. When there are 6 bits to be transfered, as shown on figure 11-3-2, if data "A" to "F" are stored to bp0 to bp5 of TXBUFn, the transmission is operated from "A" to "F".

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Figure 11-3-1 Transfer Bit Count and First Transfer Bit (starting with MSB)

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Figure 11-3-2 Transfer Bit Count and First Transfer Bit (starting with LSB)

„Receive Bit Count and First Transfer Bit

When the transfer bit count is 1 bit to 7 bits, the data storing method to the received data buffer RXBUFn is different depending on the first transfer bit selection. At MSB first, data are stored to the lower bits of RXBUFn. When there are 6 bits to be transfered, as shown on figure 11-3-3, if data "F" to "A" are stored to bp0 to bp5 of RXBUFn. At LSB first, data are stored to the upper bits of RXBUFn. When there are 6 bits to be transfered, as shown on figure 11-3-4, if data "A" to "F" are stored to bp2 to bp7 of RXBUFn.

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Figure 11-3-3 Receive Bit Count and Transfer First Bit (starting with MSB bit)

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Figure 11-3-4 Receive Bit Count and Transfer First Bit (starting with LSB bit)

Operation XI - 23

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Panasonic F77G, MN101C77C user manual TXBUFn