| ??? 11/10/05 13:55 Read: times |
#103524 - Any reason opposite? Worked out that way Responding to: ???'s previous message |
Hello Anil, Sloodan, Jan and all,
It never dawned upon me that hooking the inputs of 74LS251 and 74LS138 were opposite. In fact I thought the inputs were the same. It comes out in the wash because the LEDs are mounted on a front panel PCB which is perpendicular to the motherboard and hand wired between the two. This gives you the option of correcting any mistakes of the LED sequencing (74LS138) and frequency input order (74LS251). For your information there is another sequencing problem which was in the communication software. Indication what channel is currently being scanned and displaying the results on the seven segment readouts. The output from the 74LS138 indicate real time what channel is currently being scanned. The results have to wait for the timeout period to expire before the seven segment readouts can be updated which is during the last period. Anyway the end user will never know what is going on behind the curtain and couldn't care less. He only wants to hook up a channel and measure frequency. Regards, Charles Bannister |
| Topic | Author | Date |
| fast counter | 01/01/70 00:00 | |
| using external prescaler | 01/01/70 00:00 | |
| try f120 @ 100MHz | 01/01/70 00:00 | |
| 8 channel 35 mhz counter | 01/01/70 00:00 | |
| Charles: Check C1 | 01/01/70 00:00 | |
| Schematic corrected. C1 corrected. | 01/01/70 00:00 | |
| what is different | 01/01/70 00:00 | |
| Scaling | 01/01/70 00:00 | |
| works, thanx | 01/01/70 00:00 | |
| Any reason for opposite ... | 01/01/70 00:00 | |
| does it matter? | 01/01/70 00:00 | |
| No, of course | 01/01/70 00:00 | |
Any reason opposite? Worked out that way | 01/01/70 00:00 |