Lucent Technologies MN10285K User Manual

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B.4.3.1 Serial Writer Interface Description
The microcontroller contains the following interface hardware for serial pro-

gramming of the flash ROM:

■

One 8-bit serial interface (use serial interface 1):

♦

Data transmission and reception synchronize with external clock

♦

Transmission bit LSB first

♦

Maximum clock speed 

≥

 10 MHz

♦

Positive I/O logic

■

Two I/O pins:

♦

SBT1 and SBD1 pins (with alternate I/O port functions)

When programming the memory, you need not be aware of these microcontroller 

hardware connections. However, it is vital that you take these connections into 
account when designing your target board, so that the serial writer can program 

the device correctly, and so that SBD1 and SBT1 are dedicated pins for the serial 
writer, preventing other user circuits from communicating with the device.

8-bit serial interface

(use serial interface 1)

TXD

RXC,TXC

P25, TM4IOB, SBD1

P24, TM4IC, SBT1

RXD

RST

RST