Datasheet

105
4235K–8051–05/08
AT89C51RD2/ED2
24.9.4 Command Data Stream Protocol
All commands are sent using the same flow. Each frame sent by the host is echoed by the
bootloader.
Figure 24-8. Command Flow
4800 OK - OK OK OK OK OK OK OK
9600 OK - OK OK OK OK OK OK OK
19200 OK - OK OK OK - - OK OK
38400 - - OK OK - OK OK OK
57600 - - - - OK - - - OK
115200 - - - - - - - - OK
Frequency
(MHz)
Baudrate (kHz) 8 10 11.0592 12 14.746 16 20 24 26.6
2400 OK OK OK OK OK OK OK OK OK
4800 OK OK OK OK OK OK OK OK OK
9600 OK OK OK OK OK OK OK OK OK
19200 OK OK OK OK OK OK OK OK OK
38400 - - OK OK OK OK OK OK OK
57600 - - OK - OK OK OK OK OK
115200 - - OK - OK - - - -
Table 24-8. Autobaud Performances (Continued)
Frequency
(MHz)
Baudrate (kHz) 1.8432 2 2.4576 3 3.6864 4 5 6 7.3728
Bootloader
":"
Sends First Character of the
Frame
If (not received ":")
Sends Frame (made of 2 ASCII
Gets Frame, and Sends Back Echo
for Each Received Byte
Host
Else
":"
Sends Echo and Start
Reception
Characters Per Byte)
Echo Analysis