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Gumstix Overo COMs: 70-pin connector J4 features Extended Memory Bus and MMC signals Important: Review I/O overview information posted here.
Most recent upate: May 7th to expand information in Note #6 below.
Prior update on April 8, 2010 to add note #7 below.
Gumstix Overo COM: Signals document V1.2 (March 25th, 2010) download here
Connector J4 Notes:
All logic is at 1.8V
The input range of the supply voltage is approximately 3.3V – 4.2V.
The signals of connectors J1, J4 and J5 are connected directly to the OMAP3503 without buffers.
The signals named EM_Ax and EM_Dx are connected to the OMAP GPMC interface (named GPMC_Ax and GPMC_Dx in OMAP documents).
USBH interface supports high speed USB (480MBs).
J4-46 (4030GP2_N_MMC3_CD) = Card Detect signal for MMC3. It comes from the PMIC. Expansion board schematics may refer to pin 46 as GPIO149_MMC3_CD. The correct signal name, as shown in this table, is 4030GP2_N_MMC3_CD.
The physical location of pin 1 of the J4 connector can be found on the layout PDF for the Overo COM via here.
| Comments | Signal | Pin | Pin |
Signal | Comments |
| board supply: 3.3V - 4.2V | VSYSTEM | 1 |
70 | EM_CLK | |
| board supply: 3.3V - 4.2V | VSYSTEM | 2 | 69 | EM_NBE1 | |
| |
GND |
3 | 68 | EM_WAIT0 | |
| |
EM_NCS5_ETH0 |
4 | 67 | EM_NCS6 | |
| |
EM_NCS4 | 5 | 66 | EM_NCS0 | |
| |
GPMC_nWE | 6 | 65 | EM_NBE0 | |
| |
EM_NADV_ALE | 7 | 64 | EM_NCS1 | |
| |
EM_NOE | 8 | 63 | EM_NWP | |
| |
GPIO65_ETH1_IRQ1 | 9 | 62 | EM_A9 | |
| |
GPIO64_ETH0_NRESET | 10 | 61 | EM_A4 | |
| |
EM_A2 | 11 | 60 | EM_A10 | |
| |
EM_A8 | 12 | 59 | EM_A3 | |
| |
EM_A5 | 13 | 58 | EM_A1 | |
| |
EM_A7 | 14 | 57 | EM_A6 | |
| |
EM_D2 | 15 | 56 | EM_D0 | |
| |
EM_D10 | 16 | 55 | EM_D9 | |
| |
EM_D3 | 17 | 54 | EM_D8 | |
| |
EM_D11 | 18 | 53 | EM_D1 | |
| |
EM_D4 | 19 | 52 | EM_D13 | |
| |
EM_D12 | 20 | 51 | EM_D6 | |
| |
EM_D5 |
21 | 50 | EM_D14 | |
| |
EM_D15 | 22 | 49 | EM_D7 | |
| |
GPIO13_MMC3_CMD | 23 | 48 | GPIO151_RXD1 | |
| |
GPIO148_TXD1 | 24 | 47 | GPIO150_MMC3_WP | |
| |
GPIO176_ETH0_IRQ | 25 | 46 | 4030GP2_N_MMC3_CD | Card Detect signal for MMC3. Come from PMIC |
| |
GPIO18_MMC3_D0 | 26 | 45 | GPIO173_SPI1_MISO | |
| |
GPIO174_SPI1_CS0 | 27 | 44 | GPIO172_SPI1_MOSI | |
| |
GPIO168_USBH_CPEN | 28 | 43 | GPIO171_SPI1_CLK | |
| |
GPIO14_MMC3_DAT4 | 29 | 42 | GPIO175_SPI1_CS1 | |
| |
GPIO21_MMC3_DAT7 | 30 | 41 | GPIO114_SPI1_NIRQ | |
| |
GPIO17_MMC3_D3 | 31 | 40 | GPIO12_MMC3_CLK | |
| power in from expansion board |
USBH_VBUS | 32 | 39 | GPIO20_MMC3_D2 | |
| |
GND | 33 | 38 | GPIO23_MMC3_DAT5 | |
| |
USBH_DP | 34 | 37 | GPIO22_MMC3_DAT6 | |
| |
USBH_DM | 35 | 36 | GPIO19_MMC3_D1 | |