
TM1300 Data Book
Philips Semiconductors
7-18
PRODUCT SPECIFICATION
SYNC_MASTER
Sync master.
When set, VO_IO1 and VO_IO2 are outputs. In video-refresh modes, the EVO generates horizontal and frame
timing signals on VO_IO1 and VO_IO2 respectively. In message-passing mode and data-streaming mode, this
bit should always be set so that VO_IO1 and VO_IO2 generate START and END message signals respectively.
When zero, VO_IO2 is an input. (Hardware reset default.) In video-refresh modes, VO_IO2 serves as the frame
time reference. The active edge is selected by VO_IO2_POS.
VO_IO1_POS
VO_IO2_POS
Polarity of VO_IOx_POS.
VO_IO1_POS currently has no function.
VO_IO2_POS determines the input polarity of VO_IO2.
When ‘0’, the corresponding input triggers on the negative (high-to-low) transition of the input signal.
When ‘1’, the input triggers on the positive (low-to-high) transition.
OL_EN
Overlay Enable.
Enables the YUV overlay function in video-refresh modes.
MODE
Major operating mode.
Denes the video output major operating mode, as listed in Table 7-4 on page 7-13.
BFR1_ACK
BFR2_ACK
Buffer 1 and Buffer 2 acknowledge.
When active in data-transfer modes, writing a ‘1’ to BFR1_ACK clears BFR1_EMPTY and enables Buffer 1 for
transfer until BFR1_EMPTY is set. Writing a ‘0’ to BFR1_ACK has no effect. BRF2_ACK operates similarly for
Buffer 2. Writing a ‘1’ to VO_ENABLE in data-streaming mode is the same as writing a ‘1’ to both BFR1_ACK and
BFR2_ACK, and enables both buffers 1 and 2 for transfer. Writing a ‘1’ to VO_ENABLE in message-passing mode
is the same as writing a ‘1’ to BFR1_ACK, and enables Buffer 1 for transfer. BFR2_ACK is not used in message-
passing mode, since only Buffer 1 is used.
HBE_ACK
URUN_ACK
Acknowledge HBE or URUN.
Writing a ‘1’ to these bits clears the HBE or URUN ags and resets their corresponding interrupt conditions.
YTR_ACK
Acknowledge Y threshold.
Writing a ’1’ to this bit clears the YTR ag and resets its interrupt condition. YTR signals the CPU to set new point-
ers for the next eld. If YTR_ACK is not received by the time the active image area for the next eld starts, the
URUN ag is set. Data transfer continues with the old pointer values.
BFR1_INTEN
BFR2_INTEN
HBE_INTEN
URUN_INTEN
YTR_INTEN
Enable interrupt conditions.
Enable corresponding interrupts to be generated when the BFR1_EMPTY, BFR2_EMPTY, HBE, URUN (under-
run/end of transfer), and YTR (end of eld/buffer) ags are set, respectively.
Note: BFR2_INTEN, URUN_INTEN, YTR_INTEN must be 0 in message passing mode.
LTL_END
Little-endian.
Species that data in SDRAM is stored in little-endian format. This only affects the overlay packed-image format
interpretation in video-refresh modes. Refer to Appendix C, “Endian-ness,” for details on byte ordering.
VO_ENABLE
Enable the EVO to send image data or message data to its output.
Note: This bit should not be simultaneously asserted with the RESET bit. The correct sequence to reset and
enable the EVO is as follows.
Set all VO_CTL control elds as desired, writing VO_CTL with RESET = 1, VO_ENABLE = 0.
Retain all desired values of control elds, but rewrite VO_CTL with RESET = 0, VO_ENABLE = 0.
Finally, still retaining all desired control elds, rewrite VO_CTL with RESET = 0, VO_ENABLE = 1.
Setting VO_ENABLE in video-refresh modes starts the EVO sending image data beginning with the rst pixel in
the image. Setting VO_ENABLE in data-streaming and message-passing modes starts the EVO sending data
beginning with the rst byte in Buffer 1. In video-refresh and data-streaming modes, VO_ENABLE remains set until
cleared by the CPU. In message-passing mode, VO_ENABLE is cleared when BFR1_EMPTY is set, indicating the
end of message transfer.
Note: De-asserting VO_ENABLE in video-refresh modes causes SDRAM reads to stop, but sync framing and
BFR1_EMPTY generation and interrupts remain fully operational. The transmitted active image data is undened
in this case. To fully halt video output, a software reset is required.
Table 7-6. VO_CTL register elds
Field
Description