¡ Semiconductor
MSM6889
PB Tone Transmit Mode and PB Tone Detect Mode
When PBG1 to PBG4 are externally connected to PB1 to PB4 so as to use them as 4-bit bus lines,
their tone generation timings are as shown below.
1)
PB Tone Transmit Mode
When TEN is in the digital "0" state, PB tone is generated according to Table 2.
TEN
PBG1/PB1
TPBGS
TPBGH
PBG2/PB2
PBG3/PB3
PBG4/PB4
PB
941 Hz + 1477 Hz
Figure 7
2)
PB Tone Detect Mode
AIN
PB1/PBG1
PB2/PBG2
941 Hz + 1477 Hz
852 Hz + 1209 Hz
TG
"0"
TD
"1"
"0"
"1"
"1"
"1"
PB3/PBG3
"1"
"0"
PB4/PBG4
SP
TSP
Figure 8
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