RX610 Group
11. Buses
R01UH0032EJ0120 Rev.1.20
Page 291 of 1006
Feb 20, 2013
WR assert wait (WRON)
Write data output extension
cycle (WDOFF)
Write data output extension cycle (WDOFF)
WR assert wait (WRON)
CS assert wait (CSON)
Write data output wait (WDON)
A0
A1
Write-access CS extension
cycle(CSWOFF)
Page write cycle wait
(CSPWWAIT)
Write cycle wait
(CSWWAIT)
Write data output wait (WDON)
Data write
(WR0#, WR1#, WR#)
Tw1
Tpw1
Tnm
Tpwn
Tn1
Tw2
Tend
Tend
Th
Next bus access can be started
Tdw1
Tdwn
Twn
Data bus
(D15 to D0)
External bus clock
(BCLK)
Address
(A23 to A0)
Chip select/byte control
(CSn#/BC0#, BC1#)
[Legend] n = 0 to 7
Figure 11.16 Page-Write Access Timing
Figures 11.17 and 11.18 depict examples of operations for access to a 16-bit bus space in 32 bits. The values of the wait
control registers are example settings. In practice, the register settings will correspond to the specifications of connected
devices.
D0
A0
A1
CSPRWAIT: 1
CSRWAIT: 1
CSROFF: 1
RDON: 1
Tw1
Tn1
Tend
Tend
A2
A3
Tw1
Tpw1
Tn1
Tend
Tend
D1
D2
D3
RDON: 1
RDON: 1
RDON: 1
CSRWAIT: 1
CSPRWAIT: 1
CSROFF: 1
Tpw1
Th
Normal read cycle wait (CSRWAIT): 1
CS assert wait (CSON): 0
RD assert wait (RDON): 1
Page read cycle wait (CSPRWAIT): 1
Read-access CS extension cycle (CSROFF): 1
Accessed in 32 bits
Accessed in 32 bits
Th
Data bus
(D15 to D0)
External bus clock
(BCLK)
Address
(A23 to A0)
Chip select/byte control
(CSn#/BC0#, BC1#)
[Legend] n = 0 to 7
Data read
(RD#)
Figure 11.17 Example of Page-Read Access Operation (when 16-Bit Bus Space is Accessed in 32 Bits)