| =============================================================== | |
| == BT8XXGPIO driver == | |
| == == | |
| == A driver for a selfmade cheap BT8xx based PCI GPIO-card == | |
| == == | |
| == For advanced documentation, see == | |
| == http://www.bu3sch.de/btgpio.php == | |
| =============================================================== | |
| A generic digital 24-port PCI GPIO card can be built out of an ordinary | |
| Brooktree bt848, bt849, bt878 or bt879 based analog TV tuner card. The | |
| Brooktree chip is used in old analog Hauppauge WinTV PCI cards. You can easily | |
| find them used for low prices on the net. | |
| The bt8xx chip does have 24 digital GPIO ports. | |
| These ports are accessible via 24 pins on the SMD chip package. | |
| ============================================== | |
| == How to physically access the GPIO pins == | |
| ============================================== | |
| The are several ways to access these pins. One might unsolder the whole chip | |
| and put it on a custom PCI board, or one might only unsolder each individual | |
| GPIO pin and solder that to some tiny wire. As the chip package really is tiny | |
| there are some advanced soldering skills needed in any case. | |
| The physical pinouts are drawn in the following ASCII art. | |
| The GPIO pins are marked with G00-G23 | |
| G G G G G G G G G G G G G G G G G G | |
| 0 0 0 0 0 0 0 0 0 0 1 1 1 1 1 1 1 1 | |
| 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 | |
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
| --------------------------------------------------------------------------- | |
| --| ^ ^ |-- | |
| --| pin 86 pin 67 |-- | |
| --| |-- | |
| --| pin 61 > |-- G18 | |
| --| |-- G19 | |
| --| |-- G20 | |
| --| |-- G21 | |
| --| |-- G22 | |
| --| pin 56 > |-- G23 | |
| --| |-- | |
| --| Brooktree 878/879 |-- | |
| --| |-- | |
| --| |-- | |
| --| |-- | |
| --| |-- | |
| --| |-- | |
| --| |-- | |
| --| |-- | |
| --| |-- | |
| --| |-- | |
| --| |-- | |
| --| |-- | |
| --| |-- | |
| --| |-- | |
| --| O |-- | |
| --| |-- | |
| --------------------------------------------------------------------------- | |
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
| ^ | |
| This is pin 1 | |