Texas Instruments MSP430x4xx - Manual (Page 249)

Timer_B Operation
13-17 Timer_B
Output Example − Timer in Up/Down Mode
The OUTx signal changes when the timer equals TBCLx in either count
direction and when the timer equals TBCL0, depending on the output mode.
An example is shown in Figure 13−14 using TBCL0 and TBCL3.
Figure 13−14. Output Example—Timer in Up/Down Mode
0h
TBR(max)
TBIFG
Output Mode 1: Set
Output Mode 2: Toggle/Reset
Output Mode 3: Set/Reset
Output Mode 4: Toggle
Output Mode 5: Reset
Output Mode 6: Toggle/Set
Output Mode 7: Reset/Set
TBCL0
TBCL3
EQU3
TBIFG
Interrupt Events
EQU3
EQU0
EQU3 EQU3
EQU0
Note: Switching Between Output Modes
When switching between output modes, one of the OUTMODx bits should
remain set during the transition, unless switching to mode 0. Otherwise,
output glitching can occur because a NOR gate decodes output mode 0. A
safe method for switching between output modes is to use output mode 7 as
a transition state:
BIS #OUTMOD_7,&TBCCTLx ; Set output mode=7
BIC #OUTMODx,&TBCCTLx ; Clear unwanted bits