Explanation Of Operation Of Uart1 - Fujitsu MB90895 Series Hardware Manual

15.6

Explanation of Operation of UART1

The UART1 has master/slave type connection communication function (operation mode
1: asynchronous multiprocessor mode) in addition to bidirectional serial
communication functions (operation modes 0 and 2: asynchronous normal mode and
clock synchronous mode)
I Operation of UART1
G
Operating mode
The UART1 has three types of operation modes, they can set the inter-CPU connection mode or data
communication mode.
shows operation mode of UART1.
Table 15.6-1 Operation Mode of UART1
Operating mode
Normal
0
mode
Multiprocessor
1
mode
Clock
2 synchronous
mode
-: Setting disabled
*1:"+1" is the address/data select bit (SCR1 register bit 11: A/D) used for controlling communications.
*2:During reception, only one bit can be detected as the stop bit.
Note: The UART1 operation mode 1 (asynchronous multiprocessor mode) is only used as the
master in the master/slave type connection.
G
Inter-CPU connection method
Either a 1-to-1 connection or a master/slave type connection can be selected for the inter-CPU controller.In
both cases, the data length, parity, synchronous or asynchronous mode, etc., must be the same for all
CPUs.The operation modes are selected as follows.
• For one-to-one connection, the same operation mode (either operation mode 0 as normal mode or
operation mode 2 as clock synchronous mode) must be adopted for the two CPUs. For the asynchronous
mode, select operation mode 1: asynchronous multiprocessor mode (SMR1 register bit 7, 6: MD1, MD0
= "00
bit 7, 6: MD1, MD0 = "10
• For the master/slave type connection, operation mode 1: asynchronous multiprocessor mode (SMR1
register bit 7, 6: MD1, MD0 = 0 B is set. For the master/slave type connection, operation mode 1:
No Parity
*1
8+1
8
"): for the synchronous mode select operation mode 2: clock synchronous mode (SMR1 register
B
").
B
Data length
With Parity
7 bits or 8 bits
-
-
synchronous
CHAPTER 15 UART1
Synchrono Length of Stop
us type Bit
Asynchrono
us
1 bit or 2 bits
Asynchrono
us
Clock
None
*2
461