Z80180 Datasheet, PDF (167/326 Pages) Zilog, Inc. – Z8018x Family MPU

Z 8018x Fam ily
M PU Us e r M anual
152
c. Poll the RE bit in CNTR until RE = 0.
d. Read the receive data from TRDR.
e. Repeat steps 2 to 4 for each receive data byte.
• Receive–Interrupts
a. Poll the RE bit in CNTR until RE is 0.
b. Set the RE and EIE bits in CNTR to 1.
c. When the receive interrupt occurs read the receive data from
TRDR.
d. Set the RE bit in CNTR to 1.
e. Repeat steps 3 and 4 for each receive data byte.
CSI/O Operation Timing Notes
• Transmitter clocking and receiver sampling timings are different from
internal and external clocking modes. Figure 59 to Figure 62 illustrate
CSI/O Transmit/Receive Timing.
• The transmitter and receiver is disabled TE and RE = 0) when
initializing or changing the baud rate.
CSI/O Operation Notes
• Disable the transmitter and receiver (TE and RE = 0) before
initializing or changing the baud rate. When changing the baud rate
after completion of transmission or reception, a delay of at least one
bit time is required before baud rate modification.
• When RE or TE is cleared to 0 by software, a corresponding receive
or transmit operation is immediately terminated. Normally, TE or RE
is only cleared to 0 when EF is 1.
• Simultaneous transmission and reception is not possible. Thus, TE
and RE are not both 1 at the same time.
UM005001-ZMP0400