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Project ideas
Here's one that I've always wanted to do. The idea would be to suspend a metal ball underneath a microprocessor controlled electromagnet. The micro would have to sense the ball...
Friday, 6 August 2004 - 21:54
Programming question!
Maybe it's just my imagination - but don't you just want to mirror the switches to the output ? In this case, assuming the 4 switchs are on the lower bits and so are the outputs,...
Friday, 6 August 2004 - 21:25
Knowing if battery backed-up SRAM is valid
I have a few questions. 1. How much of your SRAM do you use for variable storage ? Surely you don't use the entire 512K for variables. 2. How do you initialize your variables now...
Tuesday, 3 August 2004 - 19:54
Bestway to get 16 channel DA converter on Mega 128
With this many channels, PWM is not a good solution since the Mega128 doesn't have this many timer channels. Look at a Maxim MAX5258 or a Linear Tech LTC1665. Both of these are 8...
Tuesday, 3 August 2004 - 18:21
Can Atmega32l do division
If you do not need to divide by a variable value (a constant) then you can multiply by a binary weighted recipicol to acheive the same result. For example: Say you wanted to...
Tuesday, 3 August 2004 - 13:53
battery powered AVR
Also look at LP2950 and LP2951 series. National Semi. is one maker of this part.
Friday, 30 July 2004 - 12:35
Double Precision Floats for the Atmega128?
Even Y=MX + b will execute faster with integer math than floating point. Even if results "spill out" of shorts, or longs, multiple precision integer math can still be written that...
Thursday, 29 July 2004 - 00:15
Double Precision Floats for the Atmega128?
I will present an equation for this floating point vs integer challage. My money is on the long (32 bit) integer math for the clear winner. unsigned long a; unsigned long b;...
Wednesday, 28 July 2004 - 23:40
difference between eeprom and flash memory?
The most common floating point representation (IEEE-754) is 32 bits (4 bytes). This includes 1 bit for sign, 8 bits for exponent, and 23 bit mantisa. This would require 4000 bytes...
Tuesday, 27 July 2004 - 20:13
RS232 connection + resistors?
It is not necessary (or even advisable) to add resistors between your two RS232 devices. In a typical configuration (null modem) Txd on one device connects directly to the Rxd on...
Monday, 26 July 2004 - 02:16
SPI To Parallel .
Here is how you connect the 74HC595 to Atmel uP for serial to parallel conversion. Atmel pin__________595 pin_______595 pin description SCK______________11___________Serial data...
Sunday, 25 July 2004 - 16:15
mega16 int1 cant fire in a tight loop!
I've never had a problem with interrupts executive from a tight control loop. The interrupt request is latched in hardware and will be serviced as soon as the current instruction...
Friday, 23 July 2004 - 01:17