Author Topic: P89V51RD2 issues  (Read 2994 times)

Barry Grieves

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P89V51RD2 issues
« on: January 31, 2005, 06:51:03 pm »
The problem I had programming the V part was fixed by using a reset chip (Microchip MCP810T) instead of relying on a capacitor to VDD on the reset line.
The part still did not work properly, this was due to the micro not seeing an input pin (P3.3) going low. With the C part, the pin was going down to 0.1V, with the V part it did not go below 2V (datasheet states 0.2VDD-.1V, ie 0.9V required). I would attribute this to the pullups on the V part being stronger than on the C part.