Send Operation Description - Oki ML63611 User Manual

12.4.2 Send Operation Description

The serial port send circuit has a two-stage configuration. This consists of the send register and the send buffer
register (STBUFL/H), so it is possible to set send data to STBUFL/H while sending the previous data. When the
BFULL flag of the serial port status register (SSTAT) is 1, however, it indicates that STBUFL/H send data has not
yet been transferred to the send register. Always verify that the BFULL flag is 0 before transferring data.
(1) UART mode
The UART mode is specified by setting STMOD (bit 0 of STCON0) to "0". Figure 12-5 is the UART mode
send timing chart. The UART mode send procedure is described below. The send baud rate is set first, then
the timer, and then the send format (data bit length, parity bit, etc.) in STCON0 and STCON1. The TM3INT
signal supplied from timers 2 and 3 is the baud rate clock.
Set send data to STBUFL/H.
The send data is transferred from STBUFL/H to the send register, and send operation begins. At the
same time the serial port send interrupt request (STINT) is generated.
Verify that BFULL = "0", then after a delay of 16 µsec, set the next send data to STBUFL/H.
When send operation is complete, the send data set to STBUFL/H is transferred to the send register, and
send operation begins. At the same time the serial port send interrupt request (STINT) is generated.
Repeat operation
OPTION A (C): 1.5 V (3.0 V), Without regulator
circuit for LCD bias
the required number of times.
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ML63611 User's Manual
Chapter 12 Serial Port (SIO)
OPTION B (D): 1.5 V (3.0 V), With regulator
circuit for LCD bias