| ??? 01/16/07 10:45 Read: times |
#130864 - HW issues Responding to: ???'s previous message |
Adrian Worley said:
Yes, it is in a socket. The socket is square and has 11 pins on each side. PLCC44. There are drawings (dimensions) at the end of datasheet. The TSOP package is extremely unlikely to be socketed. Adrian Worley said:
I will look at the MAX232 part. Look for any-232. You can have second- third- fiftieth-sourced version of it, some of them called MAX232, others using different "letters". However, I don't think you need one to connect to the module - I believe it will run on "3V" UART, not RS232. Pictures of your hardware would be possible? Adrian Worley said:
Yes, I will need to write new code for the SBUF. I think I have the timer worked out for the baud rate, although with a 20MHz crystal, the best I can get is ~9600 with a 1.36% error. It would appear most sites claim that an error of less then 3% is acceptable. Only time will tell. If you don't run it via too long cables, 1.36% is OK. The rest is a reserve for various skews and delays due to cables, connectors, level convertors. As far as I can see, the first version of this particular product was released in about 2000, but the code base predates this.
You are correct that PL/M is dead and for the most, buried. The compiler I have is an Intel DOS product of 1988 vintage. The rest of the kit is held together with string and duct tape. How many lines is it (approximately)? Isn't it worth a rewrite? This might solve also the "uneven" crystal problem as a side effect, and maybe you can also migrate to some more modern '51 derivative, such as the NXP's LPC9xx... JW |
| Topic | Author | Date |
| AT89C55WD UART voltages. | 01/01/70 00:00 | |
| Level translation | 01/01/70 00:00 | |
| Thanks for that. | 01/01/70 00:00 | |
| Real? | 01/01/70 00:00 | |
| Real | 01/01/70 00:00 | |
| Reak! | 01/01/70 00:00 | |
| Voltage. | 01/01/70 00:00 | |
| Pins | 01/01/70 00:00 | |
| Pins | 01/01/70 00:00 | |
| the peculiar port structure of '51 | 01/01/70 00:00 | |
| The Socket | 01/01/70 00:00 | |
| Socket | 01/01/70 00:00 | |
| HW issues | 01/01/70 00:00 | |
| I am on the road, but someone can verify | 01/01/70 00:00 | |
| SN74LVC4245A | 01/01/70 00:00 | |
| 5V->3V conversion and vice versa | 01/01/70 00:00 | |
| If this is CMOS | 01/01/70 00:00 | |
| No insistance. | 01/01/70 00:00 | |
a link would be nice | 01/01/70 00:00 | |
| PLCC44 | 01/01/70 00:00 | |
| why AT89C55WD? | 01/01/70 00:00 | |
| Read the thread! | 01/01/70 00:00 | |
| AT89LV55? | 01/01/70 00:00 | |
| What is the blue tooth module? | 01/01/70 00:00 | |
| Module | 01/01/70 00:00 | |
| modules | 01/01/70 00:00 | |
| Modules | 01/01/70 00:00 |