| ??? 11/29/06 04:03 Read: times |
#128643 - more information Responding to: ???'s previous message |
Hi Jez, Thanks for the reply. I made the schematic there is none. 89c2051 is used with a CFT2200 Type Timer for cable to get more channels. The purpose was for a tech to learn more about CFT2200 Type converter tests. 89c2051 would go between LA7770 saw chip and read serial data bit stream.
pin 1 +5VDC pin 2 FSK Data out pin 3 Ground pin 4 Used for 22xx type only pin 5 FSK Data IN This is how they sold them on e-bay. As a tech learning tool. The only reason I purchased the circuit board was I thought it was a good buy on E-bay. All components and boards were $10. So does any one have any idea why this circuit has such as odd configuration??? I checked all my 8051 Books & the net with no luck. I also tryed to turn on the 89c2051 input by sending it a serial bit stream but it did not work. All I would like to do is see some data on my scope from a 89c2051 output port. Also code has lock bits enabled. Why would an engineer tie pins 3,4,14,15,16,17,18 & 19 all together????? You gentlemen always seem to like puzzles well this is a winner, Please give me your best guesses. Best regards, Ralph sack |
| Topic | Author | Date |
| Unknown pinouts application | 01/01/70 00:00 | |
| who can tell | 01/01/70 00:00 | |
| i did wonder why the ports were paralleled | 01/01/70 00:00 | |
| Serial Converter | 01/01/70 00:00 | |
| more information | 01/01/70 00:00 | |
| To... | 01/01/70 00:00 | |
| Yes but | 01/01/70 00:00 | |
| Hmm... | 01/01/70 00:00 | |
| What tells the scope? | 01/01/70 00:00 | |
| Nothing | 01/01/70 00:00 | |
| Level? | 01/01/70 00:00 | |
| What will happen | 01/01/70 00:00 | |
| Improper load? | 01/01/70 00:00 | |
| Jez see this | 01/01/70 00:00 | |
| Hhm, but this paralleling is widely used! | 01/01/70 00:00 | |
| Parallel MOS transistors are fine | 01/01/70 00:00 | |
| Perfectly safe? | 01/01/70 00:00 | |
| Reasonably safe | 01/01/70 00:00 | |
| What is this circuit intended to do, Ralph? | 01/01/70 00:00 | |
| What's it to do | 01/01/70 00:00 | |
What it does | 01/01/70 00:00 | |
| Just out of interest lynn, | 01/01/70 00:00 | |
| FPGA conversion cost | 01/01/70 00:00 |