MC68306 Motorola, MC68306 Datasheet - Page 94

• Manufacturer Part Number: MC68306
• Description: Integrated EC000 Processor
• Manufacturer: Motorola

DUIPL2–0—DUART Interrupt Priority Level
5.2.2 Timer Vector Register
TVEC7–0—Timer Vector
5.2.3 Bus Timeout Period Register
A programmable-period timer can generate a bus error to terminate any bus cycle after 16
to 4096 wait states, programmable in 16-wait state increments. The bus timeout timer is
enabled by the BTEN bit in the system register.
The bus timeout timer restarts between the read and write portions of a TAS indivisible
cycle.
BT7–0—Bus Timeout Period
5-4
This bit selects the interrupt priority level for the serial module.
The value set in this field supplies the vector for the DUART timer interrupt handler.
The value set in this field supplies the bus timeout timer period. The bus timeout timer
period can be calculated from the equation:
Period = (16
000 = Reserved
001 = Interrupt priority level 1
010 = Interrupt priority level 2
011 = Interrupt priority level 3
100 = Interrupt priority level 4
101 = Interrupt priority level 5
110 = Interrupt priority level 6
111 = Interrupt priority level 7
(register value +1))
RESE
FFFFFFFF
FFFFFFFC
BT7
TVEC
RESE
T:
U
7
T:
7
7
0
BT6
TVEC
U
6
6
6
0
MC68306 USER'S MANUAL
TVEC
BT5
U
5
5
5
0
EXTAL
TVEC
BT4
U
4
4
4
0
TVEC
BT3
U
3
3
1
3
TVEC
BT2
2
2
1
U
2
SUPERVISOR ONLY
SUPERVISOR ONLY
TVEC
BT1
1
1
1
U
1
TVEC
0
0
1
BT0
U
0
MOTOROLA