88 SBC329 3U VPX Single Board Computer
Publication No. SBC329-HRM/1
6.13 Timer 1 Data Bytes 0 to 3 Registers (0x65C to 0x65F)
Reads
The value read is either the current timer value or the timer load value, depending
on bit 3 of the Timer 1 Control and Status Register 1 (T1C&SR1[3]).
Register Name
Value if T1C&SR1[3] = 0 Value if T1C&SR1[3] = 1 Timer Bits
0x65C
Timer 1 Data Byte 0
(least significant byte)
Current timer
(default 0x00)
Timer load
(default 0xFF)
7 to 0
0x65D
Timer 1 Data Byte 1
Current timer
(default 0x00)
Timer load
(default 0xFF)
8 to 15
0x65E
Timer 1 Data Byte 2
Current timer
(default 0x00)
Timer load
(default 0xFF)
16 to 23
0x65F
Timer 1 Data Byte 3
(most significant byte)
Current timer
(default 0x00)
Timer load
(default 0xFF)
24 to 31
Reading byte 0 latches the upper bits of the timer value to prevent rollover.
Writes
Writes always update the timer load value, irrespective of the setting of bit 3 of the
Timer 1 Control and Status Register 1.
Register Name
Timer Bits
0x65C
Timer 1 Data Byte 0 (least significant byte) 7 to 0
0x65D
Timer 1 Data Byte 1
8 to 15
0x65E
Timer 1 Data Byte 2
16 to 23
0x65F
Timer 1 Data Byte 3 (most significant byte) 24 to 31