UNIDATA
Unidata Manual 6293 - Precision Water Level Instruments Issue 2.1
32
8.6 Register
Allocation
The Model 6541L MicroLogger operating the standard instruction set has the
following fixed memory assignments in the Hardware Register:
Address Size Description
0
1
Software Revision Number (20 onwards)
1
2
Logger runtime in milliseconds (16 bit integer)
3 1
Error
flags
4
4
Logger scan counter (32 bit integer)
8 1
Reserved
10 1
Reserved
11
2
msb of address (bits 8-23) used in LDBLK and MVBLK
instructions
13 2
Reserved
14
1
Binary states of analog channels
16
1
Analog channel (a0) unsigned low resolution
representation (8 bit)
17
1
Analog channel (a1) unsigned low resolution
representation (8 bit)
24
2
Counter channel (C0) 16-bit
32
1
Digital input values (normally high)
Bit 3 Log Start Detect:Log Start;in memory Bit set=not
detected
Bit 6 High speed serial Data 0
33
1
User Power Supply status register
Bit 0 = 1
UPS will be ON next scan
Bit 1 = 1
UPS was ON for this scan
Bit 2 = 1
UPS is currently ON
Bit 7 = 1
(set by log program) to synchronize UPS
to come on next scan (auto reset).
34 1
Arithmetic
status
register set by ADD, SUB, MUL,DIV
instructions.
Bit 2 = Arithmetic overflow
Bit 7 =
Arithmetic carry
Logic status register set by CMP (compare) instruct.
Bit 4 set Operand 1 =Operand 2
Bit 5 set Operand 1 < Operand 2 (unsigned)
Bit 6 set Operand 1 < Operand 2 (signed)
35 1
Reserved
80
6
Version 2 Software stores Scheme Name here.
200
2
Analog channel (A0) signed 16 bit channel
202
2
Analog channel (A1) signed 16 bit channel
204
2
Battery voltage measurement (A2)
