Renesas R5S72622 Manual Do Utilizador

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Section 21   IEBus
TM
 Controller 
Page 1086 of 2108 
 
R01UH0134EJ0400  Rev. 4.00 
 
 Sep 
24, 
2014 
SH7262 Group, SH7264 Group
(2)  Communications Mode 
The IEBus has three communications modes with different transfer speeds. Table 21.2 shows the 
transfer speed in each communications mode and the maximum number of transfer bytes in one 
communications frame. 
Table 21.2  Transfer Speed and Maximum Number of Transfer Bytes in Each 
Communications Mode 
Communications 
Mode 
Maximum Number 
of Transfer Bytes 
(bytes/frame) 
Effective Transfer Speed*
1
 (kbps) 
IEB
*
2
 =  
12, 18, 24*
3
, 30, 36 MHz 
IEB
*
2
 = 12.58, 18.87*
3
,  
25.16, 31.45 MHz 
16 
About 3.9 
About 4.1 
32 
About 17 
About 18 
128 
About 26 
About 27 
Notes: 
Each unit connected to the IEBus should select a communications mode prior to 
performing communications. Note that correct communications is not guaranteed if the 
master and slave units do not adopt the same communications mode. 
 
 
In the case of communications between a unit with IEB
 = 6 MHz and a unit with IEB = 
6.29 MHz, correct communications are not possible even if the same communications 
mode is adopted. Communications must be done with the same oscillation frequency. 
 
 
1.  Effective transfer speed when the maximum number of transfer bytes is transmitted. 
 
 
2.  Peripheral clock (P
), or clocks for AUDIO_X1 and AUDIO_X2 
 
 
3.  Oscillation frequency when this LSI is used 
 
(3)  Communications Address 
In the IEBus, a specific 12-bit communications address is allocated to each individual unit. A 
communications address is configured as follows.  
  Upper four bits: group number (number identifying a group to which the unit belongs) 
  Lower eight bits: unit number (number identifying individual units in a group)