Page P Sfr Access - CMOSTEK CMT2380F17 Manual

29 Page P SFR Access

CMT2380F17 builds a special SFR page (Page P) to store the control registers for MCU operation.
These SFRs can be accessed by the ISP/IAP operation with different IFMT. In page P access, IFADRH must
set to "00" and IFADRL indexes the SFR address in page P. If IFMT= 04H for Page P writing, the content in
IFD will be loaded to the SFR in IFADRL indexed after the SCMD triggered. If IFMT = 05H for Page P reading,
the content in IFD is stored the SFR value in IFADRL indexed after the SCMD triggered.
Following descriptions are the SFR function definition in Page P:

IAPLB：IAP Low Boundary
SFR Page = P
SFR Address = 0x03
7
Bit
Name
R/W
R/W
1
Reset V alue
Bit 7~0: The IAPLB determines the IAP-memory lower boundary. Since a Flash page has 512
bytes, the IAPLB must be an even number.
To read IAPLB, MCU need to define the IFADRL for SFR address in Page-P, the IFMT for mode
selection on Page-P Read and set ISPCR.ISPEN. And then write 0x46h & 0xB9h sequentially into
SCMD. The IAPLB content is available in IFD. If write IAPLB, MCU will put new IAPLB setting
value in IFD firstly. And index IFADRL, select IFMT, enable ISPCR.ISPEN and then set SCMD.
The IAPLB content has already finished the updated sequence.
The range of the IAP-memory is determined by IAPLB and the ISP Start address as listed below.
IAP lower boundary = IAPLBx256, and
IAP higher boundary = ISP start address – 1.
For example, if IAPLB=0xE0 and ISP start address is 0xF000, then the IAP-memory range is
located at 0xE000 ~ 0xEFFF.
Additional attention point, the IAP low boundary address must not be higher than ISP start address.

CKCON2：Clock Control Register 2
SFR Page = P Only
SFR Address = 0x40
7
Bit
--
Name
W
R/W
0
Reset V alue
Bit 4: IHRCOE, Internal High frequency RC Oscillator Enable. 0: Disable internal high frequency RC
oscillator.
1: Enable internal high frequency RC oscillator. If this bit is set by CPU software, it needs 32 us to have
stable output after IHRCOE is enabled.
Bit 3~2: MCKS[1:0], MCK Source Selection.。
MCK 时钟源选择
MCKS[1:0]
6 5
R/W R/W
1 1
6 5
-- -- IHRCOE
W W
0 0
OSCin =12MHz
CKMIS = [01]
CKMS0=0
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4 3
IAPLB[7:0]
R/W R/W
1 1
4 3
MCKS1
R/W R/W
1 0
CKMS0=1 CKMS0=0
CMT2380F17
2 1
R/W R/W
1 1
2 1
MCKS0 OSCS1
R/W R/W
0 0
OSCin =11.059MHz
CKMIS = [01]
CKMS0=1
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0
R/W
0
0
OSCS0
R/W
0