M38027E8FP Renesas Electronics America, M38027E8FP Datasheet - Page 27

• Manufacturer Part Number: M38027E8FP
• Description: MCU 8-Bit 740 CISC 32KB EPROM 5V 64-Pin PQFP
• Manufacturer: Renesas Electronics America

Specifications of M38027E8FP

• Package: 64PQFP
• Family Name: 740
• Maximum Speed: 8 MHz
• Ram Size: 1 KB
• Program Memory Size: 32 KB
• Operating Supply Voltage: 5 V
• Data Bus Width: 8 Bit
• Program Memory Type: EPROM
• On-chip Adc: 8-chx8-bit
• On-chip Dac: 2-chx8-bit
• Operating Temperature: -20 to 85 °C
• Number Of Timers: 4

vided by 2.
riod by the PWM prescaler, and set the period during which the
output pulse is an “H” by the PWM register.
If the value in the PWM prescaler is n and the value in the PWM
register is m (where n = 0 to 255 and m = 0 to 255) :
PWM period = 255
PULSE WIDTH MODULATION (PWM)
The 3802 group has a PWM function with an 8-bit resolution,
based on a signal that is the clock input X
Data Setting
The PWM output pin also functions as port P5
Output pulse “H” period = PWM period
24
Fig. 19 Block diagram of PWM function
X
IN
= 51
Data bus
1/2
(n+1) s (when X
(n+1)/f(X
“0”
= 0.2
(when X
“1”
Count source
selection bit
IN
(n+1)
)
IN
= 5 MHz)
IN
prescaler pre-latch
= 5 MHz)
m s
PWM prescaler
prescaler latch
m/255
IN
or that clock input di-
PWM
PWM
6
. Set the PWM pe-
Transfer control circuit
register pre-latch
PWM register
register latch
PWM
PWM
PWM Operation
When bit 0 (PWM enable bit) of the PWM control register is set to
“1”, operation starts by initializing the PWM output circuit, and
pulses are output starting at an “H”.
If the PWM register or PWM prescaler is updated during PWM
output, the pulses will change in the cycle after the one in which
the change was made.
Fig. 18 Timing of PWM cycle
PWM output
SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER
m: Contents of PWM register
n : Contents of PWM prescaler
T : PWM cycle (when X
Port P5
MITSUBISHI MICROCOMPUTERS
51
6
latch
m
255
PWM enable bit
T = [51
(n+1)
IN
= 5 MHz)
3802 Group
(n+1)] s
s
Port P5
6