W79E217A Datasheet, PDF (53/207 Pages) Winbond – 8-bit Microcontroller

Preliminary W79E217A Data Sheet
Brake Condition Table
BPEN BKCH
BRAKE CONDITION
Brake On, (Software brake and keeping brake).
Software brake condition. When active (BPEN=BKCH=0, and BKEN=1), PWM
0
0 ^{output follows PWMnB setting. This brake has no effect on PWMRUN bit;}
therefore, internal PWM generator continues to run. When the brake is released,
the state of PWM output depends on the current state of PWM generator output
during the release.
Brake On, when PWM is not running (PWMRUN=0), the PWM output condition is
follow PWMnB setting. When the brake is released (by disabling BKEN = 0), the
0
1 ^{PWM output resumes to the state when PWM generator stop running prior to}
enabling the brake.
Brake Off, when PWM is running (PWMRUN=1).
Brake On, when Brake Pin asserted, PWM output follows PWMnB setting. The
PWMRUN will be clear.
External pin brake condition. When active (by external pin), PWM output follows
1
0 _{PWMnB setting. PWMRUN will be cleared by hardware. BKF flag will be set.}
When the brake is released (by de-asserting the external pin + disabling BKEN =
0), the PWM output resumes to the state of the PWM generator output prior to
the brake.
This brake condition (by Brake Pin) causes BKF to be set, but PWM generator
1
1 continues to run. The PWM output does not follow PWMnB, instead it output
continuously as per normal without affected by the brake.
PWM 4 LOW BITS REGISTER
Bit:
7
6
5
4
3
2
1
0
PWM4.7 PWM4.6 PWM4.5 PWM4.4 PWM4.3 PWM4.2 PWM4.1 PWM4.0
Mnemonic: PWM4L
PWM4.7-0
PWM4 Low Bits Register.
Address: CFh
PROGRAM STATUS WORD
Bit:
7
6
5
4
3
2
1
0
CY
AC
F0
RS1
RS0
OV
F1
P
Mnemonic: PSW
Address: D0h
BIT NAME
FUNCTION
7 CY
Carry flag. Set for an arithmetic operation which results in a carry being
generated from the ALU. It is also used as the accumulator for the bit operations.
6 AC
Auxiliary carry: Set when the previous operation resulted in a carry (during
addition) or a borrow (during subtraction) from the high order nibble.
5 F0
User flag 0. A general purpose flag that can be set or cleared by the by software.
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Publication Release Date: December 14, 2007
Revision A3.0