SLRC400 Datasheet, PDF (105/130 Pages) NXP Semiconductors – I·CODE Reader IC

Philips Semiconductors
I•CODE Reader IC
Product Specification Rev. 2.0 November 2001
SL RC400
16.5.1.3 Timing Diagram
The following diagram shows programming of 5 bytes into the E²PROM:
NWrite
t
prg,del
Data
Write Adr Adr _Byte0
E2 LSB MSB
WriteE2
command active
E²PROM
Programming
Byte1
E2Ready
Byte2
Byte3
t _prog
Programming Byte0
Byte4
t _prog
Programming Byte1, Byte2, and Byte3
t _prog
Programming Byte4
Idle
Cmd
TxIRq
Figure 16-3: Timing Diagram for E²PROM programming
Explanation: It is assumed, that the SL RC400 finds and reads Byte 0 before the µ-Processor is able to write
Byte 1 (t_prog,del = 300 ns). This causes the SL RC400 to start the programming cycle, which needs about
t_prog = 2.9 ms. In the meantime the µ-Processor stores Byte 1 to Byte 4 to the FIFO buffer. Assuming, that the
E²PROM starting byte-address is e.g. 4C_hex then Byte 0 is stored exactly there. The SL RC400 copies the
following data bytes into the E²PROM input buffer. Copying Byte 3, it detects, that this data byte has to be
programmed at the E²PROM byte-address 4F_hex. Since this is the end of the memory block, the SL RC400
automatically starts a programming cycle. In the next turn, Byte 4 will be programmed at the E²PROM byte-
address 50_hex. Since this is the last data byte, the flags (E2Ready and TxIRq) that indicate the end of the
E²PROM programming activity will be set.
Although all data has been programmed into the E2PROM, the SL RC400 stays in the WriteE2-Command.
Writing further data to the FIFO would lead to further E²PROM programming, continuing at the E²PROM
byte-address 51_hex. The command is stopped using the Idle-Command.
16.5.1.4 Error Flags for the WriteE2 Command
Programming is inhibited for the E²PROM blocks 0 (E²PROM’s byte-address 00_hex to 0F_hex). Programming to
these addresses sets the flag AccessErr. No programming cycle is started (for the E²PROM memory
organisation refer to chapter 6.). It is strictly recommended to use only the described E²PROM address area.
105
Preliminary