Renesas R5S72621 Manual Do Utilizador

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Section 9   Bus State Controller 
 
Page 350 of 2108 
 
R01UH0134EJ0400  Rev. 4.00 
 
 Sep 
24, 
2014 
SH7262 Group, SH7264 Group
(1)  Basic Timing for Memory Card Interface 
Figure 9.39 shows the basic timing of the PCMCIA IC memory card interface. When areas 5 and 6 
are specified as the PCMCIA interface, the bus is accessed with the IC memory card interface 
according to the SA[1:0] bit settings in CS5WCR and CS6WCR. If the external bus frequency 
(CKIO) increases, the setup times and hold times for the address pins (A25 to A0), card enable 
signals (
CE1A, CE2A, CE1B, CE2B), and write data (D15 to D0) to the RD and WE signals 
become insufficient. To prevent this error, this LSI enables the setup times and hold times for 
areas 5 and 6 to be specified independently, using CS5WCR and CS6WCR. In the PCMCIA 
interface, as in the normal space interface, a software wait or hardware wait using the 
WAIT pin 
can be inserted. Figure 9.40 shows the PCMCIA memory bus wait timing. 
Tpcm1w
CKIO
A25 to A0
CExx
RD/
WR
RD
D15 to D0 
WE
D15 to D0
BS
Read
Write
Tpcm2
Tpcm1
Tpcm1w
Tpcm1w
 
Figure 9.39   Basic Access Timing for PCMCIA Memory Card Interface