Booster Pack Tips

[RobG 1,892]

Here is my tip for designing booster packs which rely on SPI.

Value line chips come with USI or USCI modules that can be used SPI comm, however, some signals are not on the same pins.

To make you booster pack compatible with all value line chips, you have to be able to swap two pins, P1.6 (SDO/UCB0SOMI) and P1.7 (SDI/UCB0SIMO,) and all you have to do is use one 2x2 header. SCLK/UCB0CLK is OK. Slave select (SS) often called chip select (CS) or slave transmit enable (STE,) is also OK since only USCI's UCB0STE is hardwired.

 

USI: short 1-2 and 3-4

USCI_B: short 1-3 and 2-4

 

If you want to go even further and add USCI_A0 to the mix, you will have to use 3 1x3 headers.

 

USI: short J5 2-3, J4 2-3, and J4 4-5

USCI_B: short J5 2-3, J4 2-4, J4 3-5

USCI_A: short J5 1-2, J4 1-2, J4 5-6

[gwdeveloper 275]

Man, this is perfect. I'll definitely be using this tip on the Booster I'm working on. I was mostly concerned with USCI, but understand that others may want to use different chips with the USI.

 

Thanks!

[RobG 1,892]

Quick note, SDO and SDI on the schematic should be labeled as SIMO (SDO) and SOMI (SDI) to avoid confusion.

[bluehash 1,581]

Thanks for the tips. I'm already using it on the OLED, but with solder jumpers.