![](http://datasheet.mmic.net.cn/370000/UPD75236GJ_datasheet_16740772/UPD75236GJ_119.png)
119
μ
PD75236
4.11 BIT SEQUENTIAL BUFFER ........... 16 BITS
The bit sequential buffer (BSB0 to BSB3) is a special data memory for bit manipulation.
Since this buffer can easily carry out bit manipulation by sequentially changing address and bit specifica-
tion, it is useful to process data having long bit lengths in bit units.
This data memory consists of 16 bits and can execute the pmem.@L addressing of bit manipulation instruc-
tions. Thus, it can indirectly specify bits with the L register. In this case, processing can be carried out by
sequentially shifting the specified bit by simply incrementing/decrementing the L register in the program loop.
Fig. 4-67 Bit Sequential Buffer Format
Remarks
In pmem.@L addressing, the specified bit shifts in accordance with the L register. The bit sequential
buffer can be operated irrespective of MBE or MBS specification.
Data manipulation is also possible by direct addressing. 1, 4 and 8-bit direct addressing can be combined
with pmem.@L addressing for applications to continuous 1-bit data input/output. In the case of 8-bit manipula-
tion, the most and least significant 8 bits each are manipulated by specifying BSB0 and BSB2, respectively.
4.12 FIP CONTROLLER/DRIVER
(1)
FIP controller/driver configuration
The
μ
PD75236 incorporates a display controller which automatically generates the digit and segment
signals by reading the display data memory contents by carrying out DMA operation and a high-voltage
output buffer which can directly drive the fluorescent display tube (FIP). The FIP controller/driver configu-
ration is shown in Fig. 4-68.
Note
The FIP controller/driver can only operate at high and intermediate speeds (PCC = 0011B or 0010B) of
the main system clock (SCC.0 = “0”). It may malfunction with any other clock or in the standby mode.
Thus, be sure to stop FIP controller operation (DSPM.3 = “0”) and then shift the unit to any other clock
mode or the standby mode.
BSB3
BSB2
BSB1
BSB0
FC3H
FC2H
FC1H
FC0H
3
2
1
0
3
2
1
0
3
2
1
0
3
2
1
0
Address
Bit
Symbol
L=F
L Register
L=C L=B
L=7
L=8
L=3
L=4
L=0
DECS L
INCS L