3 Cov Ntawv Tshaj Tawm
Lub FT800 txhawb cov txheej txheem sib txuas lus sib xws, tsis hais seb SPI los yog I2C
interface yog xaiv.
Tus FT800 siv lub 4MB chaw seem rau nraaj, kaw thiab kaw suab rau npe nrog rau
nco buffers rau siv nrog txhua tus maub los. Daim duab qhia chaw nco tau sau tseg hauv Tshooj 5 ntawm
FT800 Datasheet.
Tus tswv tsev nyeem thiab sau qhov FT800 chaw nyob chaw siv SPI los yog I²C muas. Cov no
cov muas txhais tau tias nco nyeem ntawv, Nco Kev Sau Npe, thiab Hais Sau Kev Sau Ntawv raws li piav nyob rau hauv
tom qab seem.
Ob lub interfaces siv tib qhov byte ordering. Ntau cov bytes raug xa mus ua "Little Endian". Rau
Piv txwv, lub npe REG_FREQUENCY muaj qhov default value ntawm 0x02DC6C00 tom qab pib dua. Thaum
nyeem cov nqi no, kev txiav txim siab byte hauv MCU interface yog: 0x00, 0x6Ch, 0xDC, 0x02.
Cov ntaub ntawv SPI yog xa los ntawm qhov tseem ceeb tshaj plaws ua ntej, hom kev xoom.
Cov kev sib txuas lus hauv I²C yog encapsulated hauv I²C raws tu qauv.
Rau cov lag luam SPI, txhua lw pib nrog SS_N qis qis, thiab xaus rau thaum SS_N mus siab.
Yog tsis muaj kev txwv ntawm cov ntaub ntawv ntev li ntawm ib lub lw, tsuav yog qhov chaw cim xeeb
nruam.
Kev nkag mus rau qhov chaw nyob yog ua li ntawm peb qhov kev xav hauv interface:
Cov Xwm Ceev Nyeem Ntawv
Tus Xwm Txheej Tuaj Sau Ntawv
Kev Tshaj Tawm Tsiaj
Yog tsis muaj kev qhia nyeem.
-3.1 Lub Tsev Kawm Ntawv Nyeem Ntawv
Rau cov ntawv nyeem hauv SPI, tus tswv tsev sau ob xoom khoom, ua raws li 22-ntsis chaw nyob
thiab ib tug byte dummy. Tom qab dummy byte, tus FT800 teb rau txhua tus tswv tsev byte nrog nyeem cov ntaub ntawv
bytes.
Table 3.1 FT800 Nyeem Cov Ntaub Ntawv Khaws Ntaub Ntawv Tshaj Lawm SPI
"X" = tsis tu, feem ntau teem rau 0.
Thaum lub sij hawm cov ntaub ntawv raug nyeem los ntawm FT800 ntawm MISO teeb liab, kev ua ntawm MOSI teeb liab
yog ignored.
Rau ib qho I2C nco nyeem lw, bytes tau ntim rau hauv I2C raws li hauv qab no. Ib tug dummy
byte tsis tas:
-3.2 Hwm Lus Tseem Ceeb
Rau ib lub cim xeeb sau SPI, tus tswv tsev sau ib ntsis ua raws li kev xoom me ntsis, raws li
22-ntsis chaw nyob, ua raws li cov ntaub ntawv los sau. Tag nrho cov ntaub ntawv yog streamed nrog ib tus ntiag tug xaiv.
Lus hauv no teb Tswb muaj tsis muaj diminish byte ntawm qhov chaw nyob thiab cov ntaub ntawv los sau.
Thaum lub sij hawm cov ntaub ntawv raug sau rau FT800 ntawm MOSI teeb liab, kev ua si ntawm MISO teeb liab
yog ignored.
Rau ib qho I2C nco sau lw, bytes tau ntim rau hauv I2C raws li hauv qab no:
-3.3 Kev Tshawb Fawb Sau
Rau kev sau sau ua SPI sau ntawv, tus tswv tsev sau qov qis me ntsis raws li ib qho me ntsis,
ua raws li 5-ntsis hais kom ua, ua raws li ob bytes ntawm xoom. Tag nrho cov ntaub ntawv yog dej ntws nrog ib zaug xwb
nti xaiv.
Table 3.5 FT800 Sau qhov kev ua ntawm SPI
Thaum lub sij hawm cov lus txib tau sau rau FT800 ntawm MOSI teeb liab, kev ua si ntawm MISO cov teeb liab raug suav.
Rau ib qho I2C nco sau lw, bytes tau ntim rau hauv I2C raws li hauv qab no:
Table 3.6 FT800 Sau Kom los ntawm I2C
CEEB TOOM: Tshaj tawm cov lus txib ACTIVE tsa cov FT800 los ntawm kev pw lossis sawv ntsug. Qhov ACTIVE
hais kom ua tiav los ntawm kev sau ntawv peb bytes ntawm 00h rau qhov chaw nyob ntawm zero.
Muaj tsuas yog rau rau 6 commands, yog li nws yuav txaus nyiam kom tsim ib tus neeg hu rau hauv kev ruaj ntseg rau txhua tus
ib:
| Hais kom ua | Tus nqi (nrog rau khoom 6 & 7) | Kev piav qhia |
| Fais Fab Kev | ||
| ACTIVE | 0x00 | Hloov ntawm Standby / Kev pw tsaug zog hom kom nquag hom. Sau peb bytes ntawm 00h mus rau qhov teeb meem hais kom ua |
| STANDBY | 0x41 | Muab FT800 tub ntxhais los ua homework. Moos lub qhov rooj tawm, PLL thiab Oscillator nyob twj ywm ntawm (default). |
| SLEEP | 0x42 | Muab FT800 core mus pw hom. Moos lub qhov rooj tawm, PLL thiab Oscillator tawm. |
| PWRDOWN | 0x50 | Hloov tawm 1.2V tus tswj sab hauv. Moos, PLL thiab Oscillator tawm. |
| Moos Switching | ||
| CLKEXT | 0x44 | Pab kom PLL cov tswv yim los ntawm Crystal oscillator los yog lwm cov tswv yim moos. |
| CLK 48M | 0x62 | Hloov PLL tso tawm moos mus rau 48 MHz (vim). |
| CLK36M | 0x61 | Hloov PLL tso tawm moos mus rau 36MHz. |
| Lwm yam | ||
| CORERST | 0x68 | Xa rov qab mus rau FT800 tub ntxhais. Tag nrho cov npe thiab lub xeev cav yuav rov pib dua. |
Cov lus 3.7 FT800 Lus txib