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Chapter 26 Enhanced Capture Timer (ECT16B8CV3)
MC9S12XF - Family Reference Manual, Rev.1.19
1160
Freescale Semiconductor
26.3.2.29 Pulse Accumulator B Flag Register (PBFLG)
Read: Anytime
Write used in the ag clearing mechanism. Writing a one to the ag clears the ag. Writing a zero will not
affect the current status of the bit.
NOTE
When TFFCA = 1, the ag cannot be cleared via the normal ag clearing
All bits reset to zero.
PBFLG indicates when interrupt conditions have occurred. The ag can be cleared via the normal ag
clearing mechanism (writing a one to the ag) or via the fast ag clearing mechanism (Reference TFFCA
Table 26-37. PBCTL Field Descriptions
Field
Description
6
PBEN
Pulse Accumulator B System Enable — PBEN is independent from TEN. With timer disabled, the pulse
accumulator can still function unless pulse accumulator is disabled.
0 16-bit pulse accumulator system disabled. 8-bit PAC1 and PAC0 can be enabled when their related enable
bits in ICPAR are set.
1 Pulse accumulator B system enabled. The two 8-bit pulse accumulators PAC1 and PAC0 are cascaded to form
the PACB 16-bit pulse accumulator B. When PACB is enabled, the PACN1 and PACN0 registers contents are
respectively the high and low byte of the PACB.
PA1EN and PA0EN control bits in ICPAR have no effect.
The PACB shares the input pin with IC0.
1
PBOVI
Pulse Accumulator B Overow Interrupt Enable
0 Interrupt inhibited
1 Interrupt requested if PBOVF is set
Module Base + 0x0031
76543210
R
000000
PBOVF
0
W
Reset
00000000
= Unimplemented or Reserved
Figure 26-52. Pulse Accumulator B Flag Register (PBFLG)
Table 26-38. PBFLG Field Descriptions
Field
Description
1
PBOVF
Pulse Accumulator B Overow Flag — This bit is set when the 16-bit pulse accumulator B overows from
0xFFFF to 0x0000, or when 8-bit pulse accumulator 1 (PAC1) overows from 0x00FF to 0x0000.
When PACMX = 1, PBOVF bit can also be set if 8-bit pulse accumulator 1 (PAC1) reaches 0x00FF and an active
edge follows on IC1.