CHAPTER 6 BUS CONTROL FUNCTION
User’s Manual U15109EJ3V0UD
209
6.8 Bus Timing
The V850/SC1, V850/SC2, and V850/SC3 can execute read/write control for an external device using the
following two modes.
•
Mode using DSTB, R/W, LBEN, UBEN, and ASTB signals
•
Mode using RD, WRL, WRH, and ASTB signals
Set these modes by using the BIC bit of the system control register (SYC) (see
6.2.2 (1) System control register
(SYC) (V850/SC1, V850/SC2)
).
Figure 6-8. Memory Read (1/4)
(a)
0 waits
T1
T2
T3
CLKOUT (output)
A16 to A21
Note
(output)
AD0 to AD15 (I/O)
Address
Data
Address
ASTB (output)
R/W (output)
DSTB, RD
Note
(output)
UBEN, LBEN (output)
WAIT (input)
WRH
Note
, WRL
Note
(output)
H
A1 to A15 (output)
Address
Note
Only for the V850/SC1 and V850/SC2
Remarks 1.
{
indicates the sampling timing when the number of programmable waits is set to 0.
2.
The broken lines indicate the high-impedance state.