w77e58 Winbond Electronics Corp America, w77e58 Datasheet - Page 25

• Manufacturer Part Number: w77e58
• Description: 8 Bit Microcontroller
• Manufacturer: Winbond Electronics Corp America

TIMER 2 CONTROL
TF2:
EXF2: Timer 2 External Flag: A negative transition on the T2EX pin (P1.1) or timer 2 overflow will
RCLK: Receive Clock Flag: This bit determines the serial port 0 time-base when receiving data in
TCLK: Transmit Clock Flag: This bit determines the serial port 0 time-base when transmitting data in
EXEN2: Timer 2 External Enable. This bit enables the capture/reload function on the T2EX pin if
TR2:
TIMER 2 MODE CONTROL
C T
CP RL
/ 2 : Counter/Timer Select. This bit determines whether timer 2 will function as a timer or a
/
Timer 2 overflow flag: This bit is set when Timer 2 overflows. It is also set when the count is
equal to the capture register in down count mode. It can be set only if RCLK and TCLK are
both 0. It is cleared only by software. Software can also set or clear this bit.
cause this flag to set based on the CP RL
transition, this flag must be cleared by software. Setting this bit in software or detection of a
negative transition on T2EX pin will force a timer interrupt if enabled.
serial modes 1 or 3. If it is 0, then timer 1 overflow is used for baud rate generation, otherwise
timer 2 overflow is used. Setting this bit forces timer 2 in baud rate generator mode.
modes 1 and 3. If it is set to 0, the timer 1 overflow is used to generate the baud rate clock
otherwise timer 2 overflow is used. Setting this bit forces timer 2 in baud rate generator mode.
Timer 2 is not generating baud clocks for the serial port. If this bit is 0, then the T2EX pin will
be ignored, otherwise a negative transition detected on the T2EX pin will result in capture or
reload.
Timer 2 Run Control. This bit enables/disables the operation of timer 2. Clearing this bit will
halt the timer 2 and preserve the current count in TH2, TL2.
counter. Independent of this bit, the timer will run at 2 clocks per tick when used in baud rate
generator mode. If it is set to 0, then timer 2 operates as a timer at a speed depending on
T2M bit (CKCON.5), otherwise it will count negative edges on T2 pin.
2 :Capture/Reload Select. This bit determines whether the capture or reload function will be
used for timer 2. If either RCLK or TCLK is set, this bit will be ignored and the timer will
function in an auto-reload mode following each overflow. If the bit is 0 then auto-reload will
occur when timer 2 overflows or a falling edge is detected on T2EX pin if EXEN2 = 1. If this
bit is 1, then timer 2 captures will occur when a falling edge is detected on T2EX pin if EXEN2
= 1.
Mnemonic: T2CON
Mnemonic: T2MOD
Bit:
Bit:
TF2
7
HC5
7
EXF2
6
HC4
6
RCLK
5
HC3
- 25 -
5
/
2 , EXEN2 and DCEN bits. If set by a negative
TCLK
4
HC2
4
EXEN2
Preliminary W77E58
T2CR
Publication Release Date: March 1999
3
3
Address: C8h
Address: C9h
TR2
2
2
-
C T
T2OE
/ 2
1
1
Revision A1
CP RL
DCEN
0
/
0
2