4 MEMORY AND BUS
4-8
Seiko epson Corporation
S1C17F13 TeChniCal Manual
(Rev. 1.0)
7.1 Internal RAM Size Selections
Table 4.
MSCIRAMSZ.IRAMSZ[2:0] bits
Internal RAM size
0x7
Reserved
0x6
(16KB)
*
0x5
(12KB)
*
0x4
6KB
0x3
4KB
0x2
2KB
0x1
1KB
0x0
512B
*
Setting prohibited in this IC
FlaShC Flash Read Cycle Register
Register name
Bit
Bit name
Initial
Reset
R/W
Remarks
FLASHCWAIT
15–8 –
0x00
–
R
–
7
XBUSY
0
H0
R
6–2 –
0x00
–
R
1–0 RDWAIT[1:0]
0x0
H0
R/WP
Bits 15–8 Reserved
Bit 7
XBuSY
This bit indicates whether the Flash memory can be accessed or not.
1 (R):
Flash memory ready to access
0 (R):
Flash access prohibited
The Flash memory can always be accessed during normal operation.
Bits 6–2
Reserved
Bits 1–0
RDWaiT[1:0]
These bits set the number of bus access cycles for reading from the Flash memory.
7.2 Setting Number of Bus Access Cycles for Flash Read
Table 4.
FLASHCWAIT.RDWAIT[1:0] bits Number of bus access cycles
System clock frequency
0x3
4
20.0 MHz (max.)
0x2
3
20.0 MHz (max.)
0x1
2
16.3 MHz (max.)
0x0
1
8.2 MHz (max.)
note
: Be sure to set the FLASHCWAIT.RDWAIT[1:0] bits before the system clock is configured.