NEC PD78078 User Manual
492
CHAPTER 20 SERIAL INTERFACE CHANNEL 2
Figure 20-15. Period that Reading Receive Buffer Register is Prohibited
T1 : The amount of time for one unit of data sent in the baud rate selected with the baud
rate generator control register (BRGC) (1/baud rate)
T2 : The amount of time for 2 clocks of 5-bit counter source clock (f
SCK
) selected with
BRGC
Example of countermeasures
An example of the countermeasures is shown below.
[Condition]
f
X
= 5.0 MHz
Processor clock control register (PCC) = 00H
Oscillation mode selection register (OSMS) = 01H
Baud rate generator control register (BRGC) = B0H (when 2400 bps is selected for baud rate)
T
CY
= 0.4
µ
s (t
CY
= 0.2
µ
s)
1
T1 =
= 416.7
µ
s
2400
T2 = 12.8 x 2 = 25.6
µ
s
T1 + T2
= 2212 (clock)
t
CY
RxD (input)
INTSR
INTSER (when framing or
overrun error is generated)
overrun error is generated)
INTSER (when parity error
is generated)
is generated)
D0
T1
T2
D1
D2
D6
D7
STOP
START
Parity