Digi NS9215 Computer Hardware User Manual


 
SYSTEM CONTROL MODULE
Timer 6–9 Control registers
168 Hardware Reference NS9215
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Timer 6–9 Control registers
Addresses: A090 01A8 / 01AC / 01B0 / 01B4
D09:06 R/W TCS 0x0 Timer clock select
0000 AHB clock x 2
0001 AHB clock
0010 AHB clock / 2
0011 AHB clock / 4
0100 AHB clock / 8
0101 AHB clock / 16
0110 AHB clock / 32
0111 AHB clock / 64
1000 AHB clock / 128
1111 External event
D05:04 R/W Timer mode 1 0x0 Timer mode 1
00 Internal timer or external event
01 External low-level gated timer
10 External high-level gated timer
11 Concatenate the lower timer.
Note: When either external gated option is
selected, the time clock select bits deter-
mine the frequency.
D03 R/W Int Sel 0x0 Interrupt select
0 Interrupt disable
1 Generate IRQ
D02 R/W Up Down 0x0 Up/Down select
0 Up counter
1 Down counter
D01 R/W Bit timer 0x0 32 or 16 bit timer
0 16-bit timer
1 32-bit timer
D00 R/W Rel Enbl 0x0 Reload enable
0 Halt at terminal count. The timer must be
disabled, then enabled to reload the timer when
the terminal count is reached.
1 Reload and resume count at terminal count
Bits Access Mnemonic Reset Description