projects / linux-2.6-block.git / blame
| Commit | Line | Data |
|---|---|---|
| ff1d5c2f MB |
1 | =============================================================== |
| 2 | == BT8XXGPIO driver == | |
| 3 | == == | |
| 4 | == A driver for a selfmade cheap BT8xx based PCI GPIO-card == | |
| 5 | == == | |
| 6 | == For advanced documentation, see == | |
| 7 | == http://www.bu3sch.de/btgpio.php == | |
| 8 | =============================================================== | |
| 9 | ||
| 10 | ||
| 11 | A generic digital 24-port PCI GPIO card can be built out of an ordinary | |
| 12 | Brooktree bt848, bt849, bt878 or bt879 based analog TV tuner card. The | |
| 13 | Brooktree chip is used in old analog Hauppauge WinTV PCI cards. You can easily | |
| 14 | find them used for low prices on the net. | |
| 15 | ||
| 16 | The bt8xx chip does have 24 digital GPIO ports. | |
| 17 | These ports are accessible via 24 pins on the SMD chip package. | |
| 18 | ||
| 19 | ||
| 20 | ============================================== | |
| 21 | == How to physically access the GPIO pins == | |
| 22 | ============================================== | |
| 23 | ||
| 24 | The are several ways to access these pins. One might unsolder the whole chip | |
| 25 | and put it on a custom PCI board, or one might only unsolder each individual | |
| 26 | GPIO pin and solder that to some tiny wire. As the chip package really is tiny | |
| 27 | there are some advanced soldering skills needed in any case. | |
| 28 | ||
| 29 | The physical pinouts are drawn in the following ASCII art. | |
| 30 | The GPIO pins are marked with G00-G23 | |
| 31 | ||
| 32 | G G G G G G G G G G G G G G G G G G | |
| 33 | 0 0 0 0 0 0 0 0 0 0 1 1 1 1 1 1 1 1 | |
| 34 | 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 | |
| 35 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
| 36 | --------------------------------------------------------------------------- | |
| 37 | --| ^ ^ |-- | |
| 38 | --| pin 86 pin 67 |-- | |
| 39 | --| |-- | |
| 40 | --| pin 61 > |-- G18 | |
| 41 | --| |-- G19 | |
| 42 | --| |-- G20 | |
| 43 | --| |-- G21 | |
| 44 | --| |-- G22 | |
| 45 | --| pin 56 > |-- G23 | |
| 46 | --| |-- | |
| 47 | --| Brooktree 878/879 |-- | |
| 48 | --| |-- | |
| 49 | --| |-- | |
| 50 | --| |-- | |
| 51 | --| |-- | |
| 52 | --| |-- | |
| 53 | --| |-- | |
| 54 | --| |-- | |
| 55 | --| |-- | |
| 56 | --| |-- | |
| 57 | --| |-- | |
| 58 | --| |-- | |
| 59 | --| |-- | |
| 60 | --| |-- | |
| 61 | --| O |-- | |
| 62 | --| |-- | |
| 63 | --------------------------------------------------------------------------- | |
| 64 | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
| 65 | ^ | |
| 66 | This is pin 1 | |
| 67 |