As a descendant of a simulated world, I often hear some comments on the porch, on the issues of digital simulation of how designers do not understand. Digital designers have mercilessly criticized the analog IC Designer. The two camps hold unless the participants to break boundaries, into the mixed-signal research in the area.
Simulation of typical spirit, not all converters with the same data format. Convert unsigned binary types used, other converter using a signed binary complement data. Even more Nikon D40 Battery Charger
complex problems, the converter output 12-bit or 14-bit data, there are 16-bit output. There is another 24-δ-σ conversion technology.
Whatever the purpose of the simulation results. For the purposes of these converters, ADC position of the least significant bit is the 8-bit, 16-bit or 32-bit No. 0 of word processors. Analog circuit designers, this is of great significance. However, the 12-bit converter is the sign bit of the processor's 11. If 16-bit width of the variable c to the converter output values, assuming that the c symbol is 15. Processors from the converter identifies negative, all data from of bipolar 12-bit ADC is positive. Because the sign bit is in the wrong location.
You could take a few steps to solve the problem. First of all, read-modify-write procedure, the processor data transfer in the register. Read CPU registers that contain data, move the data to the necessary location, and then write that data back into memory. Transposition of DSP to complete in one clock cycle. Controller requires a lot of clock cycles to complete the process of transposition. If you use this control policy, be careful of buffer is not continuous. This means that the cache cannot tell if a Panasonic Lumix DMC-FP7 Battery Charger
DMA controller to write new data to memory. The result, CPU cache of old data and shift operation. Need to keep in mind is that whenever he moved a bit to the left, has meant that the ADC conversion result by 2.
Another way is to move data to the right in your processor cycles. Disadvantages of this approach uses CPU and require additional instruction. Another option is the converter directly connected to the processor data bus. If you are 12-bit converters attached to 11th and 15th on the processor bus, then the symbol will be in the correct position. And 11th to 14th position of the data gets zero complete data, these data are uncertain. This method applies only to the parallel interface. In this scenario, the DMA-based mobile data transfer is not required.
Than users who use the serial port and parallel port users are lucky because most of the processor's serial ports to receive "left believing that zero-padded to the minimum significant digits" or "extended sign bit to the most significant bit to the right" features. This feature significantly reduces CPU processing data in memory. Number of serial ports only work when the receive data length is a power of 2, for example, 16-bit data length. These ports do not work at 12, 14 or 24-bit data length.
Simulation engineers to help handle the processor interface problems. As far as I know, the processor is 8-bit, 16-bit or 32-bit, I've never heard of a 12-bit or 14-bit processor. Unless all of the analog chip JVC AA-VF8 Battery Charger
design by breaking through the boundaries, otherwise design digital interface for granted. Read the ADC data sheet, position of the check to the digital interface transport. If the ADC data interface does the initial check, then you would start paying for more success.