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User’s Manual U16890EJ1V0UD
494
CHAPTER 18 CLOCKED SERIAL INTERFACE A (CSIA) WITH
AUTOMATIC TRANSMIT/RECEIVE FUNCTION
In the V850ES/KG1, two channels of clocked serial interface A (CSIA) with automatic transmit/receive function are
provided.
18.1 Functions
CSIAn has the following two modes.
3-wire serial I/O mode
3-wire serial I/O mode with automatic transmit/receive function
(1) 3-wire serial I/O mode
This mode is used to transfer 8-bit data using three lines: a serial clock pin (SCKAn) and two serial data pins
(SIAn and SOAn).
In addition, whether 8-bit data is transferred MSB or LSB first can be specified, so this interface can be
connected to any device.
(2) 3-wire serial I/O mode with automatic transmit/receive function
This mode is used to transfer 8-bit data using three lines: a serial clock pin (SCKAn) and two serial data pins
(SIAn and SOAn).
In addition, whether 8-bit data is transferred MSB or LSB first can be specified, so this interface can be
connected to any device.
Data can be transferred to/from a display driver etc. without using software since a 32-byte buffer RAM is
incorporated for automatic transfer.
Maximum transfer speed: 2 MHz (in master mode)
Master mode/slave mode selectable
Transfer data length: 8 bits
MSB/LSB-first selectable for transfer data
Automatic transmit/receive function:
Number of transfer bytes can be specified between 1 and 32
Transfer interval can be specified (0 to 63 clocks)
Single transfer/repeat transfer selectable
On-chip dedicated baud rate generator (6/8/16/32 divisions)
3-wire SOAn: Serial data output
SIAn: Serial data input
SCKAn: Serial clock I/O
Transmission/reception completion interrupt request signal: INTCSIAn
Internal 32-byte buffer RAM (used in 3-wire serial I/O mode with automatic transmit/receive function)
Remark
n = 0, 1