
34
Am79C30A/32A Data Sheet
Map Mode Register 3 — (MMR3) — Read/Write
Address Indirect 6CH
Secondary Tone Ringer Amplitude Register — (STRA) — Read/Write
Address = Indirect 6DH
Table 35.
Map Mode Register 3
Bit
4
X
0
1
0
1
0
1
0
1
X
X
X
X
X
X
X
X
Function
X Bit 7 Reserved, must be written to 0
X 0-dB pre-amplifier gain, 1.250-V maximum peak input voltage
X +6-dB pre-amplifier gain, 0.625-V maximum peak input voltage
X +12-dB pre-amplifier gain, 0.312-V maximum peak input voltage
X +18-dB pre-amplifier gain, 0.156-V maximum peak input voltage
X +24-dB pre-amplifier gain, 0.078-V maximum peak input voltage
X Reserved; undefined
X Reserved; undefined
X Reserved; undefined
X MUTE ON, AINA and AINB inputs disabled
X MUTE OFF, AINA or AINB enabled
X Digital Loopback 2 enabled; D/A output looped to A/D input; EAR, LS, and AIN pin disabled
X Digital Loopback 2 disabled
X EAR and LS simultaneously enabled
X EAR or LS enabled by MMR2 bit 1
1 Secondary Tone Ringer enabled
0 Secondary Tone Ringer disabled
7
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
6
X
0
0
0
0
1
1
1
1
X
X
X
X
X
X
X
X
5
X
0
0
1
1
0
0
1
1
X
X
X
X
X
X
X
X
3
X
X
X
X
X
X
X
X
X
1
0
X
X
X
X
X
X
2
X
X
X
X
X
X
X
X
X
X
X
1
0
X
X
X
X
1
X
X
X
X
X
X
X
X
X
X
X
X
X
1
0
X
X
0
Table 36.
Secondary Tone Ringer Amplitude
Bit
Peak-to-Peak
Output Voltage
Silent
Reserved
Reserved
Reserved
Reserved
Reserved
0.22 V
0.31 V
0.44 V
0.62 V
0.88 V
1.25 V
1.77 V
2.50 V
3.53 V
5.00 V
Bits 0–3 Reserved;
must be written to 0
Relative Output
Approximate Power
into 50 ohms
7
0
0
0
0
0
0
0
0
1
1
1
1
1
1
1
1
6
0
0
0
0
1
1
1
1
0
0
0
0
1
1
1
1
5
0
0
1
1
0
0
1
1
0
0
1
1
0
0
1
1
4
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
3
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
2
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
1
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
–27 dB
–24 dB
–21 dB
–18 dB
–15 dB
–12 dB
–9 dB
–6 dB
–3 dB
0 dB
0.25 mW
0.5 mW
1.0 mW
2.0 mW
4.0 mW
8.0 mW
16.0 mW
31.25 mW
62.5 mW
125.0 mW
X
X
X
X
0
0
0
0