![](http://datasheet.mmic.net.cn/260000/PPSMMANUAL_datasheet_15946768/PPSMMANUAL_68.png)
12-8
UUART Communication Support
Programmer’s Manual
Data Transmit
with RTS/CTS
flow control
APPLICATION
PPSM
H/W
Figure 12-4 UART Communication Architecture - Data Transmit with RTS/CTS flow control
Request
Access
Check
Access
Permission
Release
Access &
Acknowledge
Send Data To
Hardware &
Acknowledge
Request
Transmit
Access Permission Request
(if not already)
Granted / Denied
Complete / Error
Release Access Request
Data Sent
Acknowledge
Release
Access
Assert RTS
and
Initiate TX
timeout
Pull Low RTS pin
Check
transmit
Permission
Granted / Denied
Wait for end
of
transmission
Transmit Request & Data
Negate RTS
and
Clear TX
timeout
Pull High RTS pin
Personal Portable System Manager
Programmer’s Manual
12-9
12.1.3
UART Interface Interrupt Message
The UART interface communicates with an application via an interrupt message
returned by IrptGetData(), called IRPT_UART. Please refer to Chapter 15 -
Interrupt Handlingfor details about IrptGetData().
After an application is granted permission to use the UART, it can initiate a data
transmission request. As the data transmission progressed, it will receive the
IRPT_UART interrupt message with the corresponding message data under the
following circumstances.
An error condition has occurred. The interrupt message data,
UART_ERROR, appended with an error code will be returned to
the calling application. The error codes are:
UART_ERR_TMOUT for data transmission time out condition
once the transmission has started.
UART_ERR_FRAME for frame error condition during data
receive.
UART_ERR_PARITY for parity error condition during data
receive.
UART_ERR_OVERRUN for overrun error condition during data
receive.
UART_ERR_NODATA for prematurely requesting PPSM for
data before data has been received.
Data has been received from the UART. The interrupt message
data, UART_DATA_RECEIVED, will be returned to the calling
application.
Data send request has been completed. The interrupt message
data, UART_DATA_SENT, will be returned to the calling
application.
Table 12-1
shows the new UART interrupt message and the related data returned
with it during IrptGetData().
12.2
UART Configurations
PPSM allows applications to configure the UART to operate in normal or IrDA
Table 12-1 UART Interrupt Message and related Message Data
Interrupt Message
Data Returned
Data Type
IRPT_UART
UART_ERROR followed by the actual
error code:
F
Freescale Semiconductor, Inc.
For More Information On This Product,
Go to: www.freescale.com
n
.