Casio LK-270 User Manual
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19.3.13
len : Data Length
As shown below, the meaning of this field differs depending on whether an individual transfer or a bulk parameter set
transfer is being performed.
Individual Parameter Transfer
Data length indicates the length of the array being transferred minus 1 when the parameter contains a character string or
other similar array structure.
Bulk Parameter Set Transfer
Data length indicates the number of bytes of data included within a packet. When this value is zero, it means there is no
actual data.
19.3.14
data : Parameter Data
Parameter data indicates the parameter value. Data that is the size of the number of arrays equivalent to len + 1 follows.
For the structure of one data item, the length depends on the data bit width, as shown below.
Each block of data is packed from the lowest order byte first. In the case of multiple-byte data, the lowest weighted bit
is the LSB of the first "data" block, and the highest weighted bit is the MSB of the final "data" block. The following
shows an example of how data would be divided for transfer in the case of 32-bit data.
19.3.15
Single Parameter Data Size Limit
With the Instrument's system exclusive message format, the size of a single message cannot exceed 256 bytes. The data
size and the array size, however, can cause a packet to exceed 256 bytes when transferring a single parameter array. In
this case, the IPS and IPR message data length and data index number values can be modified to enable division of a
single parameter value into multiple messages so it can be sent that way.
Format: 0lllllllB (LSB) 0mmmmmmmB (MSB)
Format: 0dddddddB
(0eeeeeeeB)
(0fffffffB)
(0gggggggB)
(0hhhhhhhB)
:
:
dddddB + 1
Number of Data
1 - 7
1
8 - 14
2
15 - 21
3
22 - 28
4
29 - 32
5
7
6
5
4
3
2
1
0
data0:
0
[bit06]
[bit05]
[bit04]
[bit03]
[bit02]
[bit01]
[bit00]
data1:
0
[bit13]
[bit12]
[bit11]
[bit10]
[bit09]
[bit08]
[bit07]
data2:
0
[bit20]
[bit19]
[bit18]
[bit17]
[bit16]
[bit15]
[bit14]
data3:
0
[bit27]
[bit26]
[bit25]
[bit24]
[bit23]
[bit22]
[bit21]
data4:
0
0
0
0
[bit31]
[bit30]
[bit29]
[bit28]