8PSK Stuff
The goal here is to use the Dish Network 8PSK adapter for other purposes - it's very cheap ($99) and has the amaizing BCM 4500 chip which according to their docs does DVB QPSK, DIRECTV QPSK , DCII QPSK plus QPSK, 8PSK and 16QAM using Turbo coding. Turbo coding is the FEC and this is more robust than the traditional Viterbi algorithm. Do a Google search on Turbo Code for more info.
I want to build two things from this board: a) a cheapo USB controlled tuner with a DVB-SPI output. I have an SPI to ASI converter to then be able to get at the data and b) want to hack a Twinhan card and replace the MPEG bus coming from their tuner with the data out from this tuner - again probably a USB interface to control the 8PSK stuff.
Connections
Edge Connector
| A1 | CLK | B1 | SYNC |
| A2 | GND | B2 | GND |
| A3 | VALID | B3 | ERROR |
| A4 | DATA | B4 | DATA |
| A5 | GND | B5 | GND |
| A6 | DATA | B6 | DATA |
| A7 | DATA | B7 | DATA |
| A8 | DATA | B8 | DATA |
| A9 | GND | B9 | GND |
| A10 | SDA | B10 | SCLK |
| A11 | B11 | ||
| A12 | B12 | ||
| A13 | B13 | N/C | |
| A14 | GND | B14 | GND |
| A15 | B15 | 3.3V | |
| A16 | N/C | B16 | 3.3V |
| A17 | GND | B17 | GND |
| A18 | N/C | B18 | 5V |
| A19 | GND | B19 | 5V |
| A20 | LNB POWER | B20 | GND |
| A21 | GND | B21 | GND |
| A22 | GND | B22 | GND |
| A23 | GND | B23 | GND |
| A24 | GND | B24 | GND |
| A25 | GND | B25 | GND |
Pins with a blank space have connections but their purpose is not yet known. I suspect one of them is the output enable for the MPEG data since the receiver shares the bus the 8VSB module.
I don't yet know the order of the DATA pins but the other MPEG signals (VALID, ERROR, SYNC, CLK) all appear to be regular DVB style that could drive straight to DVB-SPI with balanced drivers.
Internal Connectors
There are a few internal connectors that I suspect are used when testing the board during the manufacturing process:
J5 (I2C interface)
| 1 | SDA |
| 2 | SCLK |
| 3 | RESET to BCM4500 |
| 4 | I2C address select? |
J6 (Power interface)
| 1 | 3.3V |
| 2 | GND |
| 3 | +5V |
| 4 | GND |
| 5 | LNB POWER |
J3 (MPEG from BCM4500)
| 1 | DATA |
| 2 | GND |
| 3 | DATA |
| 4 | GND |
| 5 | DATA |
| 6 | GND |
| 7 | DATA |
| 8 | GND |
| 9 | DATA |
| 10 | GND |
| 11 | DATA |
| 12 | GND |
| 13 | DATA |
| 14 | GND |
| 15 | DATA |
| 16 | GND |
| 17 | CLOCK |
| 18 | GND |
| 19 | VALID |
| 20 | GND |
| 21 | SYNC |
| 22 | GND |
| 23 | ERROR |
| 24 | GND |
Tuning Results
I've tuned:
NDA Stuff
I have an NDA with Broadcom. This allows me to know how to communicate with the BCM 4500 and what it's pinout is etc. I cannot tell anyone how to communicate with this chip, it's operation, pinout, AC characteristics and all that kind of thing. All the information here is relative to the Dish Network 8PSK adapter design which I am free to discuss. Signal names shown here are the result of observing the operation of the Dish Network 8PSK adapter with a scope.
Pictures
Click for full-size.
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Top left: Dish acuator controller Bottom left: Custom interface - 3V to TLL conversion and 3V to RS-232 conversion Bottom middle: DeVaSys USB controller. This moves the dish and communicates via serial interfaces to a BLSA connected to a Sharp tuner and to the Sharp tuner via another microcontroller. The controller also has an I2C interface which is used to talk to the BCM 4500 Right: Dish Network 6000 receiver with 8PSK module. |
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| Close up of the 8PSK module and the DeVaSys controller. The three wires going to the 8PSK board are GND, SCLK and SDA. The Dish Network reeceiver needs to be powered on so it receives a signal and then powered off with the remote control followed by hitting the Sys Info button on the remote control. This puts the receiver in a mode where it doesn't talk over the I2C bus to the tuner so we can with the controller since I2C is open collector. |
Random Notes
Don't get exited about the DCII receive capability. All DCII streams are scrambled - even those that are free to view on DCII receivers.