| ??? 07/23/07 17:33 Read: times |
#142191 - The infamous boot vector corruption problem! |
Background: Got a production board that has a P89C51RB2 (or 51RB2H) on it. Manufacturing complains that a small percentage (this time it was ~20 units out of 500) refuse to program. Only about 60 to 70 percent programmed right away, with the remainder requiring one or two power cyclings to get them to enter ISP.
Investigation: Took 5 of the 20 units that refused to program and unsoldered the micro's. Checked the micro's in a parallel programmer, and lo and behold, all their boot vector bytes are corrupted! Here's the kicker: the reset controller is a MAX810. Supposedly, I thought, a reliable reset generator. So what can I check to verify this issue? Is it due to the timing between the +5V and the reset signal? Should I use an open-collector reset controller instead of the totem-pole MAX810? Thanks. tom |
| Topic | Author | Date |
| The infamous boot vector corruption problem! | 01/01/70 00:00 | |
| numbers | 01/01/70 00:00 | |
| an issue | 01/01/70 00:00 | |
| wrong device -> "screwup" | 01/01/70 00:00 | |
| Eureka! | 01/01/70 00:00 | |
| Statistics | 01/01/70 00:00 | |
| it was not him... | 01/01/70 00:00 | |
| on the mechanism and the decline of NXP | 01/01/70 00:00 | |
some more material to chew on | 01/01/70 00:00 |