Iota » History » Version 7
laforge, 02/19/2016 10:48 PM
1 | 1 | laforge | This is the Analog Baseband Chip TWL3025 |
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2 | 2 | laforge | |
3 | 7 | laforge | It consists of various functions, including |
4 | * ADC and DAC for the GSM baseband signals |
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5 | * ADC and DAC for the Voice/Audio path |
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6 | * DAC for APC (Automatic Power Control) |
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7 | * DAC for AFC (Automatic Frequency Control) |
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8 | * Battery Charging Controller |
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9 | * LDO's (Linear Power Regulators) |
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10 | 1 | laforge | |
11 | 7 | laforge | The functions of the ABB are controlled by a register set. The register set |
12 | is available through both USP and BSP. |
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13 | |||
14 | == External Interfaces == |
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15 | === USP (uController Serial Port) === |
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16 | |||
17 | 4 | laforge | This is the SPI-like control interface between DBB and the TWL3025 (ABB). |
18 | 3 | laforge | |
19 | 1 | laforge | [[Image(Iota:twl3025_usp.png)]] |
20 | 2 | laforge | |
21 | 7 | laforge | === TSP (Timee Serial Port) === |
22 | 1 | laforge | |
23 | 7 | laforge | It is connected to the TSP controller inside the [wiki:Calypso] DBB. |
24 | |||
25 | 2 | laforge | The CLK6.5 Signal makes things a bit more complicated than we would like. The sequence of events is something like: |
26 | 7 | laforge | * CLK_13M is applied continuously to TWL3025 |
27 | 2 | laforge | * nTEN is in default state of high (inactive) |
28 | * internal CLK6.5 is in default state low |
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29 | * nTEN is asserted low by TPU, some 0..65ns before CLK_13M rising edge |
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30 | * next CLK13M falling edge starts first CLK6.5 rising edge |
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31 | * every falling edge of CLK13M toggles CLK6.5 |
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32 | * TDR is sampled at every rising edge of CLK6.5 (including the first edge above) |
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33 | 1 | laforge | * 7 bits are transferred during seven rising edges of CLK6.5 |
34 | * TEN stays asserted for 1 CLK13M period after last bit is transferred |
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35 | * TEN needs to be released before next CLK13M rising edge to prevent another transfer |
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36 | 7 | laforge | |
37 | === BSP (Baseband Serial Port) === |
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38 | |||
39 | This synchronous serial port is connected to the RIF (Radio InterFace) of the Calypso DBB. |