SM39A16M1 Datasheet, PDF (31/104 Pages) SyncMOS Technologies,Inc – Additional Baud Rate Generator for Serial port

SM39A16M1
8-Bit Micro-controller
16KB with ISP Flash
& 1K+256B RAM embedded
6. Multiplication Division unit
This on-chip arithmetic unit provides 32-bit division, 16-bit multiplication, shift and normalize features. All operations are
unsigned integer operation.
Mnemonic Description
PCON
ARCON
MD0
MD1
MD2
MD3
MD4
MD5
Power control
Arithmetic
Control register
Multiplication/Divi
sion Register 0
Multiplication/Divi
sion Register 1
Multiplication/Divi
sion Register 2
Multiplication/Divi
sion Register 3
Multiplication/Divi
sion Register 4
Multiplication/Divi
sion Register 5
Direct
87H
EFh
E9h
EAh
EBh
ECh
EDh
EEh
Bit 7 Bit 6 Bit 5 Bit 4
Multiplication Division Unit
SMOD MDUF
-
-
MDEF MDOV SLR
Bit 3
-
MD0[7:0]
MD1[7:0]
MD2[7:0]
MD3[7:0]
MD4[7:0]
MD5[7:0]
Bit 2 Bit 1
-
STOP
SC[4:0]
Bit 0
IDLE
RESET
40H
00H
00H
00H
00H
00H
00H
00H
6.1 Operating registers of the MDU
The MDU is handled by eight registers, which are memory mapped as special function registers. The arithmetic unit
allows operations concurrently to and independent of the CPU’s activity. Operands and results registers are MD0 to
MD5. Control register is ARCON. Any calculation of the MDU overwrites its operands.
Mnemonic: ARCON
7
6
5
4
MDEF MDOV SLR
3
2
1
SC[4:0]
Address: EFh
0 Reset
00H
MDEF- Multiplocation Division Errot Flag.
The MDEF is an error flag. The error flag is read only. The error flag indicates an improperly performed
operation (when one of the arithmetic operations has been restarted or interrupted by a new operation).
The error flag mechanism is automatically enabled with the first write to MD0 and disabled with the
final read instruction from MD3 multiplication or shift/normalizing) or MD5 (division) in phase three.
The error flag is set when:
Phase two in process and write access to MDx registers (restart or interrupt calculations)
The error flag is reset only if:
The second phase two finished (arithmetic operation successful completed) and read access to MDx
registers.
MDOV - Multiplication Division Overflow flag. The overflow flag is read only.
The overflow flag is set when:
1. Division by Zero
2. Multiplication with a result greater then 0000FFFFh
Specifications subject to change without notice contact your sales representatives for the most recent information.
ISSFD-M069
Ver E SM39A16M1 04/20/2015
- 31 -