WTS701 Datasheet, PDF (27/77 Pages) Winbond – WINBOND SINGLE-CHIP TEXT-TO-SPEECH PROCESSOR

WTS701
PWUP
Byte Sequence:
Description:
Class 0
Type I
Host controller
0x02
0x00
WTS701
Status Byte 0
Status Byte 1
Wake up the WTS701 processor to IDLE state.
CONV
Convert
The convert command starts the text to speech conversion process. The convert command is followed
by ASCII text data. The device has a buffer of 256 bytes. When this buffer is full, the chip pulls the
R/ B line LOW and sets the BFUL bit in the status word indicating that the WTS701 buffer manager is
in the buffer full condition. The WTS701 remains in the buffer full condition until the input buffer has
been emptied of half the buffer space (128 bytes). When the buffer is full, the Host may do one of
three things:
1. The Host may end the command at that point, then poll the BFUL bit of the SPI status register until
it is clear, and then send new CONV commands with the additional ASCII text data.
2. The Host may also continue the command (keep SS LOW) and wait for the R/ B pin to go HIGH.
As each word is processed by the WTS701, space will become free in the buffer and the R/ B pin
will go HIGH until it is full again.
3. The device may also be configured such that it will generate an interrupt to the host when the buffer
threshold (set by RCOM command) has been crossed. (See Tables 3 and 4) This allows the host
to fill the buffer then wait for the Interrupt to send the additional data.
During conversion, the Convert Count Register is updated as each word has been spoken. This
register is cleared to zero at power up, and at the beginning of a new conversion process after one
has been terminated.
A convert command is terminated in several ways:
• Send a finish command (FIN) indicating that the host has finished sending data. In this case,
the device finishes converting the text buffer, then stops and enters a wait state.
• The conversion process will also stop when the EOT (^D, ASCII 0x1A, UNICODE/Big5 0x00
0x1A) character is part of the input text. When the device detects the EOT character, it will
continue the conversion process until the buffer is emptied and the final word spoken. Then it
will stop and enter the wait state.
• The finish word command (FINW) will cause the WTS701 device to finish the word currently
being spoken, then flush the buffers and enter the wait state.
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Publication Release Date: May 2003
Revision 3.09