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Echelon I/O Model Reference for Smart Transceivers and Neuron Chips User Manual

Page 114

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104

Serial I/O Models

Parity is not supported for this model. The application code can use bit I/O pins

for flow control handshaking if required.

STA

R

T

STA

R

T

STO

P

Figure 37. Serial Input and Timing

Table 37. Serial Input Latency Values for Series 3100 Devices

Symbol

Description

Typical at 10 MHz

t

fin

Function call to input sample
Min (first sample)

Max (timeout)


67 μs

20 byte frame

t

ret

Return from function

10 μs

The duration of this function call is a function of the number of data bits

transferred and the transmission bit rate. t

fin

(max) refers to the maximum

amount of time this function waits for a start bit to appear at the input. After

this time, the function returns a 0 as data. t

fin

(min) is the time to the first

sampling of the input pin. For example, the timeout period at 2400 bits/second is
(20 x 10 x 1/2400) + t

fin

(min).