Motor de Búsqueda de Datasheet de Componentes Electrónicos |
|
CAT34RC02UITE13 Datasheet(PDF) 6 Page - Catalyst Semiconductor |
|
CAT34RC02UITE13 Datasheet(HTML) 6 Page - Catalyst Semiconductor |
6 / 16 page CAT34RC02 6 Doc. No. 1052, Rev. I WRITE OPERATIONS Byte Write In Byte Write mode the Master creates a START condition, and then broadcasts the Slave address, byte address and data to be written. The Slave acknowledges the three bytes by pulling down the SDA line during the 9th clock cycle following each byte. The Master creates a STOP condition after the last ACK from the Slave, which then starts the internal write operation (Fig. 6). During internal write, the Slave will ignore any read/write request from the Master. Page Write The CAT34RC02 contains 256 bytes of data, arranged in 16 pages of 16 bytes each. The page is selected by the four most significant bits of the address byte presented to the device after the Slave address, while the four least significant bits point to the byte within the page. By ‘loading’ more than one data byte into the device, up to an entire page can be written in one write cycle (Fig. 7). The internal byte address counter will increment after each data byte. If the Master transmits more than 16 data bytes, then earlier bytes will be overwritten by later bytes in a ‘wrap-around’ fashion within the selected page. The internal write cycle is started following the STOP condition created by the Master. Acknowledge Polling Acknowledge polling can be used to determine if the CAT34RC02 is busy writing or is ready to accept commands. Polling is implemented by sending a ‘Selective Read’ command (described under READ OPERATIONS) to the device. The CAT34RC02 will not acknowledge the Slave address, as long as internal write is in progress. WRITE PROTECTION Hardware Write Protection With the WP pin held HIGH, the entire memory, as well as the SWP flags are protected against WRITE operations (Fig. 9). If the WP pin is left floating or is grounded. then it has no impact on the operation of the CAT34RC02. Software Write Protection The lower half of memory (first 128 bytes) can be protected against WRITE operations by setting one of two Software Write Protection (SWP) flags/switches. The PSWP (Permanent Software Write Protection) flag can be set but not cleared by the user. The RSWP (Reversible Software Write Protection) flag can be set and cleared by the user. Whereas the PSWP flag can be set ‘in-system’, the RSWP flag is meant to be used during testing. RSWP commands require the presence of a very high voltage (higher than VCC) on address pin A0 and fixed logic levels for the other two address pins. The CAT34RC02 is shipped ‘unprotected’. The state of the SWP flags can be read by issuing an ‘Immediate Address Read’ command, with the Slave address ‘preamble’ set to 0110 (6h) instead of the ‘normal’ 1010 (Ah). A SWP READ will return the complemented versions of the two flags in the last two slots of the resulting data byte; the other six more significant bits in the data byte have no meaning to the user (Fig. 11). Figure 7. Page Write Timing BYTE ADDRESS SLAVE ADDRESS S A C K A C K DATA A C K S T O P P BUS ACTIVITY: MASTER SDA LINE S T A R T BUS ACTIVITY: MASTER SDA LINE DATA n+P BYTE ADDRESS (n) A C K A C K DATA n A C K S T O P S A C K DATA n+1 A C K S T A R T P SLAVE ADDRESS NOTE: IN THIS EXAMPLE n = XXXX 0000(B); X = 1 or 0 Figure 6. Byte Write Timing |
Número de pieza similar - CAT34RC02UITE13 |
|
Descripción similar - CAT34RC02UITE13 |
|
|
Enlace URL |
Política de Privacidad |
ALLDATASHEET.ES |
¿ALLDATASHEET es útil para Ud.? [ DONATE ] |
Todo acerca de Alldatasheet | Publicidad | Contáctenos | Política de Privacidad | Intercambio de Enlaces | Lista de Fabricantes All Rights Reserved©Alldatasheet.com |
Russian : Alldatasheetru.com | Korean : Alldatasheet.co.kr | Spanish : Alldatasheet.es | French : Alldatasheet.fr | Italian : Alldatasheetit.com Portuguese : Alldatasheetpt.com | Polish : Alldatasheet.pl | Vietnamese : Alldatasheet.vn Indian : Alldatasheet.in | Mexican : Alldatasheet.com.mx | British : Alldatasheet.co.uk | New Zealand : Alldatasheet.co.nz |
Family Site : ic2ic.com |
icmetro.com |