E62655RUSB Renesas Electronics America, E62655RUSB Datasheet - Page 183

• Manufacturer Part Number: E62655RUSB
• Description: EMULATOR BASE H8S/2655R W/USB
• Manufacturer: Renesas Electronics America
• Type: Microcontrollerr

Specifications of E62655RUSB

• Contents: E6000 Emulator Unit and 4 Logic Probes
• For Use With/related Products: H8S/2655R
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

6.3.2
The external space bus specifications consist of three elements: bus width, number of access
states, and number of program wait states.
The bus width and number of access states for on-chip memory and internal I/O registers are
fixed, and are not affected by the bus controller.
(1) Bus Width
(2) Number of Access States
(3) Number of Program Wait States
Table 6.3 shows the bus specifications for each basic bus interface area.
A bus width of 8 or 16 bits can be selected with ADWCR. An area for which an 8-bit bus is
selected functions as an 8-bit access space, and an area for which a 16-bit bus is selected
functions as a16-bit access space.
If all areas are designated for 8-bit access, 8-bit bus mode is set; if any area is designated for
16-bit access, 16-bit bus mode is set. When the burst ROM interface is designated, 16-bit bus
mode is always set.
Two or three access states can be selected with ASTCR. An area for which 2-state access is
selected functions as a 2-state access space, and an area for which 3-state access is selected
functions as a 3-state access space.
With the DRAM/PSRAM interface and burst ROM interface, the number of access states may
be determined without regard to ASTCR.
When 2-state access space is designated, wait insertion is disabled.
When 3-state access space is designated by ASTCR, the number of program wait states to be
inserted automatically is selected with WCRH and WCRL. From 0 to 3 program wait states
can be selected.
Bus Specifications
Rev. 5.00 Sep 14, 2006 page 153 of 1060
Section 6 Bus Controller
REJ09B0331-0500