Cypress S6E2C1 Series, Руководство пользователя

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Serial Programming Connection
S6E2CC/C5/C4/C3/C2/C1 Series Flash Programming Specification, Document Number: 002-04913 Rev. *D 65
When external clock is used as the source oscillation clock
Figure 3-3 shows a connection example of FS-232C I/F when an external clock is used as a source oscillation clock.
When external clock is used, the communication will start with a baud rate of 115200[bps]. Table 3-2 shows available
frequencies and communication baud rates at start-up.
When external clock is used, there is a restriction below.
- If user system needs to use X1 pin as GPIO and cannot make the pin open, the clock oscillation may be unstable.
When the X1 pin cannot be opened, please use built-in high-speed CR oscillator for reliable communication.
Figure 3-3 Connection Example When External Clock is Used
Table 3-2 Available Oscillating Frequency and Communication Baud Rate at Start-Up for Clock Asynchronous
Serial Communication
Source Oscillating Frequency Communication Baud Rate at Start-Up
4 MHz 9600 bps
8 MHz 19200 bps
16 MHz 38400 bps
24 MHz 57600 bps
48 MHz 115200 bps
RS-232C
driver
P21/SIN0_0
VSS
P60
VCC
INITX
P22/SOT0_0
Note: The pull-up resistance values shown are for example. Select the most appropriate resistance values for each system.
MD1
MD0
Device
●
●
●
Serial write: 0
Serial write: 1
10
kΩ
X0
X1
●
10
kΩ
●
●
●
Serial write at UART
communication mode: 0
10
kΩ
10
kΩ
RS-232C
User system
External
Clock
Open