A project log for a battery-powered data logger contains three separate claims
PHYSICS · Multi-part · Fermi University Physics · Electronics, Instrumentation & Communication · Digital electronics, embedded systems and data acquisition · Digital electronics, embedded systems and data acquisition
Inside the Instrument, Ch Microcontrollers and programmable logic for measurement
Problem
A project log for a battery-powered data logger contains three separate claims. Find the error in each and give the correct statement; for claim
((a)) support the correction with a number. (a) The controller samples at 6250 samples per second and sends two-byte samples over a 115200-baud serial link (ten bits per byte, so the link carries 11520Bs−1 on average). The data rate is 12500Bs−1, above the link's average rate. The log reads: "we changed the transmit buffer from 64 bytes to 512 bytes and this solved the problem permanently."
((b)) Inside one process clocked on the rising edge, a 4-bit up-counter with a synchronous enable is written as two lines: line 1, if enable='1' then count <= count + 1; and line 2, output <= count;. The engineer expects that on a clock edge where enable is high, output already shows count+1 on that same edge, "because line 1 runs before line 2, just like a program."
((c)) A firmware log states: "the sampling handler and the serial handler have both run without a single dropped or delayed sample for a week on the bench, so the design meets its worst-case response-time requirement and needs no further check."