5 timer b mode: pwm output function, 7 .1 .5 timer b mode: pwm output function -5, Table 7-2 . timer b pwm output function -5 – Maxim Integrated MAXQ610 User Manual

Page 108: Figure 7-4 . timer b clock output mode -5, Maxq610 user’s guide, Table 7-2. timer b pwm output function

7-5

MAXQ610 User’s Guide

7.1.5 Timer B Mode: PWM Output Function

The PWM output function is enabled whenever the TBCS:TBCR bit pair is nonzero . Table 7-2 shows how these bits
define a certain output function .
When the PWM output function is configured to the reset mode, configuring TBC = 0000h disables the TBC compare
match reset operation . The timer will do one set on 0000h and never reset . When the PWM output function is configured
to the set mode, configuring TBC = TBR disables the TBC compare match set operation . The timer will do one reset
on TBR match and never set . When the PWM output function is configured to toggle, configuring TBC = 0000h or TBR
disables the toggle function .
When the timer is not running (TRB = 0), the initial output starting state of the TBB output is established as low or high,
respectively, if the reset function (TBCR = 1,TBCS = 0) or set function (TBCR = 0, TBCS = 1) is established . Invoking
the toggle function does not change the already defined starting state for TBB, thus a fixed high or low starting state
may be defined for the toggle mode by first passing through the set or reset mode . The initial starting state takes effect
on the pin when the timer is started (TRB = 1) . Changing the output function to set or reset while the timer is running
does not affect the current output .

Figure 7-4. Timer B Clock Output Mode

Table 7-2. Timer B PWM Output Function

*The initial state for the toggle mode depends on the previous set or reset mode. This means that the TBCS:TBCR bits should be

configured to set or reset momentarily when changing from “Compare Disable” to “Compare Toggle Mode” to establish a specific

starting state.

EXFB

TIMER B INTERRUPT

TOGGLE

TFB

TBA PIN

TBR

0000h

TBV

TRB

SYSTEM

CLOCK

PRESCALER

TBPS[2:0]

C/TB = 0

TBOE = 1

TBA FREQUENCY OUT = PRESCALED SYSTEM CLOCK/(2 x (TBR + 1))

FALLING

EDGE

TBB PIN

EXENB

TBCS:TBCR

FUNCTION

INITIAL STATE (TRB = 0)

None (Compare Disable)

No change

01 (Reset)

Reset on TBC Match, Set on 0000h

Low

10 (Set)

Set on TBC Match, Reset on TBR Match

High

11 (Toggle)

Toggle on TBC Match (except TBR or 0h)

No change*