
2-90
7/9/98
UART
7600 Series
M37640E8-XXXF Preliminary Specification
Mitsubishi Microcomputers
2.14 UART
This chip contains two identical UARTs. Each UART has the following main features:
Clock selection:
Φ
or SCSGCLK
Prescaler selection:
x1/x8/x32/x256 divisions (both
Φ
and SCSGCLK)
Baud rate:
11.4 bits/second - 750 Kbytes/second (at
Φ
= 12MHz)
Error detection:
parity/framing/overrun/error sum
Parity:
odd/even/none
Stop bits:
1 or 2
Character length:
7, 8, or 9 bits
Transmit/receive buffer:
2 stages (double buffering)
Handshaking:
Clear-to-Send (CTS) and Request-to-Send (RTS)
Interrupt generation conditions: Transmit Buffer Empty or Transmit Complete, Receive Buffer
full and Receive Error Sum.
Address mode for multi-receiver environment
The following descriptions apply to both UARTs.
The UART receives parallel data from the core or DMAC, converts it into serial data, and transmits
the results to the send data output terminal UTXDx. The UART receives serial data from an external
source through the receive data input URXDx, converts it into parallel data, and makes it available to
the core or DMAC. The UART can detect parity, overrun, and framing errors in the input stream and
report the appropriate status information. A double buffering configuration is used for the UART’s
transmit and receive operations. This double buffering is accomplished by the use of a transmit buffer
and transmit shift register on the transmit side and the receive buffer and receive shift register on the
receive side.
Address
UART1 Description
Acronym and
Value at Reset
Address
UART2 Description
Acronym and
Value at Reset
0030
16
0031
16
0032
16
0033
16
0034
16
0035
16
0036
16
UART1 mode register
UART1 baud rate generator
UART1 status register
UART1 control register
UART1 transmit/receiver buffer 1
UART1 transmit/receiver buffer 2
UART1 RTS control register
U1MOD=00
U1BRG=XX
U1STS=03
U1CON=00
U1TRB1=XX
U1TRB2=XX
U1RTSC=00
0038
16
0039
16
003A
16
003B
16
003C
16
003D
16
003E
16
UART2 mode register
UART2 baud rate generator
UART2 status register
UART2 control register
UART2 transmit/receiver buffer 1
UART2 transmit/receiver buffer 2
UART2 RTS control register
U2MOD=00
U2BRG=XX
U2STS=03
U2CON=00
U2TRB1=XX
U2TRB2=XX
U2RTSC=00
Pin
Description
Pin
Description
UTXD1P8
4
URXD1P8
5
UART1 CTS1 pin is multiplexed with
P8
6
UART1 RTS1 pin is multiplexed with
P8
7
UTXD2
UART2 transmit pin is multiplexed with
P8
0
URXD2P8
1
UART2 CTS2 pin is multiplexed with
P8
2
UART2 RTS2 pin is multiplexed with
P8
3
CTS1
CTS2
RTS1
RTS2