I'm trying to use the module VADC of Vybrid intending to capture some video PAL frames.
Here are the test conditions:
- I used the Vybrid Reference Manual Rev. 5, 07/2013 to configure all the registers
- Toradex Module VF61 with a MVF61NS151CMK50 chip
- 4 Input VADC discoupled with 47nF e 75ohm to ground signal
- A standard PAL signal on each input channel originated from a SONY videocamera
- PLL6 configured to 1064 MHz according to the 9-3 RM table
- PLL6 divided by 2 through the CCM_CACRR[PLL6_DIV_CLOCK] register
- PLL6 configured as a source of the VADC through the CCM_CSCMR1[VADC_CLK_SEL]register
- Clock of the VADC divided by 4 through the CCM_CSCDR1[VADC_DIV] register to obtain 133MHz
- Chosen VCAFE_VIN_0 through the AFE_INPFLT[mux_enlf] register
- Set pull-down VCAFE_VIN_1, VCAFE_VIN_2, VCAFE_VIN_3 through the AFE_OFFDRV[input_pulldown_en] register
- Enabled the clock to VADC through the CCM_CSCDR1[VADC_EN] register
- Introduced a 500ms delay
Reading the VDEC_VIDMOD[PAL detected] register I always obtain a 0 value: unrecognized PAL .
Furthermore I read the VDEC_VIDMOD[m625] register always active, with or without input signal.
So, why is the VDEC_VIDMOD[PAL detected] register always null, nevertheless I connected a signal?
Is it necessary to configure some other register (AFE or VDEC) so that the VADC system could recognize the PAL standard?