69 vdp fifo interrupt threshold register, 70 vdp fifo reset register, 71 vdp fifo output control register – Texas Instruments TVP5147M1PFP User Manual
Page 72: 72 vdp line number interrupt register
Functional Description
64
SLES140A—March 2007
TVP5147M1PFP
2.11.69 VDP FIFO Interrupt Threshold Register
Subaddress
BDh
Default
80h
7
6
5
4
3
2
1
0
Threshold [7:0]
Threshold [7:0]: This register is programmed to trigger an interrupt when the number of words in the FIFO
exceeds this value.
NOTE: 1 word equals 2 bytes.
2.11.70 VDP FIFO Reset Register
Subaddress
BFh
Default
00h
7
6
5
4
3
2
1
0
Reserved
FIFO reset
FIFO reset: Writing any data to this register clears the FIFO and VDP data register (CC, WSS, VITC and VPS).
After clearing, this register is automatically cleared.
2.11.71 VDP FIFO Output Control Register
Subaddress
C0h
Default
00h
7
6
5
4
3
2
1
0
Reserved
Host access enable
Host access enable: This register is programmed to allow the host port access to the FIFO or to allow all VDP
data to go out the video output.
0 = Output FIFO data to the video output Y[9:2] (default)
1 = Allow host port access to the FIFO data
2.11.72 VDP Line Number Interrupt Register
Subaddress
C1h
Default
00h
7
6
5
4
3
2
1
0
Field 1 enable
Field 2 enable
Line number [5:0]
Field 1 interrupt enable:
0 = Disabled (default)
1 = Enabled
Field 2 interrupt enable:
0 = Disabled (default)
1 = Enabled
Line number [5:0]: Interrupt line number (default 00h)
This register is programmed to trigger an interrupt when the video line number exceeds this value in bits [5:0].
This interrupt must be enabled at address F4h.
NOTE: The line number value of 0 or 1 is invalid and does not generate an interrupt.