Motorola DSP56305 User Manual page 636

PROGRAMMING REFERENCE
Application:
Timers
Timer Reload Mode Bit 9
0 = Timer operates as a free
running counter
1 = Timer is reloaded when
selected condition occurs
Direction Bit 11
0 = TIO pin is input
1 = TIO pin is output
Data Input Bit 12
0 = Zero read on TIO pin
1 = One read on TIO pin
Data Output Bit 13
0 = Zero written to TIO pin
1 = One written to TIO pin
Prescaled Clock Enable Bit 15
0 = Clock source is CLK/2 or TIO
1 = Clock source is prescaler output
Timer Compare Flag Bit 21
0 = "1" has been written to TCSR(TCF),
or timer compare interrupt serviced
1 = Timer Compare has occurred
Timer Overflow Flag Bit 20
0 = "1" has been written to TCSR(TOF),
or timer Overflow interrupt serviced
1 = Counter wraparound has occurred
23 22 21 20 19 18 17 16
* * TCF TOF *
0 0 0
Timer Control/Status Register
TCSR0:$FFFF8F Read/Write
TCSR1:$FFFF8B Read/Write
TCSR2:$FFFF87 Read/Write
Reset = $000000
Figure D-20 Timer Control/Status Register (TCSR)
D-36
Inverter Bit 8
0 = 0- to-1 transitions on TIO input increment the counter,
or high pulse width measured, or high pulse output on TIO
1 = 1-to-0 transitions on TIO input increment the counter,
or low pulse width measured, or low pulse output on TIO
15 14 13 12 11 10 9
* * * PCE * DO
0 0 0 0
DSP56305 User's Manual
Timer Control Bits 4 – 7 (TC0 – TC3)
TC (3:0) TIO Clock
0000 GPIO Internal
0001 Output Internal
0010 Output Internal
0011 Input External
0100 Input Internal
0101 Input Internal
0110 Input Internal
0111 Output Internal
1000 –
1001 Output Internal
1010 Output Internal
1011 –
1100 –
1101 –
1110 –
1111 –
Timer Overflow Interrupt Enable Bit 1
0 = Overflow Interrupts Disabled
1 = Overflow Interrupts Enabled
Timer Compare Interrupt Enable Bit 2
0 = Compare Interrupts Disabled
1 = Compare Interrupts Enabled
8 7
DI DIR * TRM INV TC3 TC2
0
*
Date:
Programmer:
Sheet 2 of 3
Mode
Timer
Timer Pulse
Timer Toggle
Event Counter
Input Width
Input Period
Capture
Pulse Width Modulation
– Reserved
Watchdog Pulse
Watchdog Toggle
– Reserved
– Reserved
– Reserved
– Reserved
– Reserved
Timer Enable Bit 0
0 = Timer Disabled
1 = Timer Enabled
6 5 4 3 2 1
TC1 TC0 * TCIE TQIE
0
= Reserved, Program as 0
MOTOROLA
0
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