Intel386™ EX EMBEDDED MICROPROCESSOR USER’S MANUAL
13-8
Figure 13-7. SSIO Transmitter with Autotransmit Mode Disabled
The SSIO Unit can be operated either by using a polling method or through interrupts.
•Figure 13-8 shows a basic flowchart for using the polling metho d to transmit data through
the SSIO.
•Figure 13-9 shows a basic flowchart for the Interrupt Service Routine necessary when usi ng
interrupts to transmit data through the SSIO. If interrupts are used, follow the below
sequence for initialization:
1. Initialize the SSIO.
2. Initialize the interrupts - ICU initialization, Interrupt Service Routine, etc.
3. Unmask the interrupts on the ICU.
A3399-01
HOLD
Data Written Into
SSIOTBUF
Clears THBE
TEN = 1
THBE = 0
THBE = 1
Initialize
SSIO
T
E
N
=
0
TUE
Set
TUE = 1
TEN = 1
THBE = 1
Data In Buffer
Moved To
Shift Register
THBE Set