mc68hc908gp20 Freescale Semiconductor, Inc, mc68hc908gp20 Datasheet - Page 257

• Manufacturer Part Number: mc68hc908gp20
• Description: M68hc08 Family Of 8-bit Microcontroller Units Mcus
• Manufacturer: Freescale Semiconductor, Inc

18.5.2.5 Inversion of Transmitted Output
18.5.2.6 Transmitter Interrupts
MC68HC908GP20
Freescale Semiconductor
NOTE:
—
Rev 2.1
When queueing an idle character, return the TE bit to logic 1 before the
stop bit of the current character shifts out to the TxD pin. Setting TE after
the stop bit appears on TxD causes data previously written to the SCDR
to be lost.
Toggle the TE bit for a queued idle character when the SCTE bit
becomes set and just before writing the next byte to the SCDR.
The transmit inversion bit (TXINV) in SCI control register 1 (SCC1)
reverses the polarity of transmitted data. All transmitted values, including
idle, break, start, and stop bits, are inverted when TXINV is at logic 1.
(See
These conditions can generate CPU interrupt requests from the SCI
transmitter:
•
•
18.9.1 SCI Control Register
SCI transmitter empty (SCTE) — The SCTE bit in SCS1 indicates
that the SCDR has transferred a character to the transmit shift
register. SCTE can generate a transmitter CPU interrupt request.
Setting the SCI transmit interrupt enable bit, SCTIE, in SCC2
enables the SCTE bit to generate transmitter CPU interrupt
requests.
Transmission complete (TC) — The TC bit in SCS1 indicates that
the transmit shift register and the SCDR are empty and that no
break or idle character has been generated. The transmission
complete interrupt enable bit, TCIE, in SCC2 enables the TC bit to
generate transmitter CPU interrupt requests.
1.)
Advance Information
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