| Richard Erlacher 10/17/11 03:03 Read: 132 times Denver, Co USA |
#184232 - Here's a thought ... Responding to: Per Westermark's previous message |
IIRC, the old Motorola MC6821 PIA had bit-configurable I/O. Now, I wouldn't suggest using one of those, unless your 805x is very slow. However, I see that, on Opencores.org, there's a VHDL model of the 6821. You might not want to utiize the entire model, but the I/O portion might suit you, and, of course, you're free to increase or decrease the I/O's and feature set.
Would that address your need for bit-configurable I/O? If you use the model as-is, it might allow you to do some experimenting before you wade in and customize it to your needs. Further, with a 5-volt-tolerant CPLD or FPGA, you might find it fast enough and capable of handling your level-shifting need as well. RE |
| Topic | Author | Date |
Bit-configurable transceiver chips  | Per Westermark | 09/12/11 02:28 |
| Suggesting....again... | Michael Karas | 09/12/11 05:35 |
| Alas 5V needed and ribbon cables are a bit "rough" | Per Westermark | 09/12/11 06:54 |
| Another Suggestion.... | Michael Karas | 09/12/11 05:59 |
| level translator | Jan Waclawek | 09/12/11 06:21 |
| Alas, "weak output drive" and no input hysterese | Per Westermark | 09/12/11 07:30 |
| TI sn74gtl2010 | Stefan KAnev | 09/17/11 02:18 |
| or NXP GTL2010,GTL2000 | Stefan KAnev | 09/19/11 01:24 |
| looks promising | Richard Erlacher | 09/21/11 22:29 |
| NXP GTL20xx -> NVT20xx | Jan Waclawek | 10/04/11 00:57 |
| Need to read more to understand them | Per Westermark | 09/20/11 02:04 |
| looks like the cat's miauw | Erik Malund | 09/21/11 07:45 |
| NXP has .... | Erik Malund | 09/12/11 13:28 |
| I2C or SPI just can't get even close to the huge bandwidth | Per Westermark | 09/12/11 14:01 |
| nope, no I²C clocks | Erik Malund | 09/12/11 14:21 |
| extender, not expander | Per Westermark | 09/12/11 14:37 |
| I have been wondering this myself | Justin Fontes | 09/12/11 16:18 |
| Supported capacitance seems to be the snag | Per Westermark | 09/12/11 17:23 |
| Differential SPI | Jez Smith | 09/16/11 09:39 |
| Serial -> buffers on adapter boards is a potential solution | Per Westermark | 09/16/11 14:41 |
| Have you considered programmable logic? | Richard Erlacher | 09/19/11 14:08 |
| I had suggested this as well | Michael Karas | 09/19/11 14:33 |
| Yes ... I remember that ... | Richard Erlacher | 09/19/11 23:43 |
| Long life | Per Westermark | 09/20/11 01:59 |
| They seem to live a long time ... | Richard Erlacher | 09/20/11 09:22 |
| Adapters | Per Westermark | 09/20/11 10:16 |
| These aren't necessarily so "huge" | Richard Erlacher | 09/20/11 19:52 |
| Not huge in size | Per Westermark | 09/21/11 01:49 |
| Some of them can handle that. | Richard Erlacher | 09/21/11 22:34 |
| Yes and no | Per Westermark | 09/22/11 04:53 |
| There are ways ... | Richard Erlacher | 09/22/11 10:55 |
| Body diodes | Per Westermark | 09/22/11 16:39 |
| serial termination ... | Erik Malund | 09/23/11 07:36 |
| Yes, current- and bandwidth-limiting components used | Per Westermark | 09/23/11 08:25 |
| you youing whippersnappers, pay attention | Erik Malund | 09/23/11 11:45 |
| pedantry, again | Andy Peters | 09/20/11 11:13 |
| What would YOU suggest? | Richard Erlacher | 09/20/11 19:45 |
| Here's a thought ... | Richard Erlacher | 10/17/11 03:03 |
| Probably | Per Westermark | 10/17/11 15:51 |
I'd sugest you consider older CPLD's | Richard Erlacher | 10/17/11 19:14 |