"lvalue required as left operand of assignment" When Writing to GPIO_REGs

[Fuzzyzilla]

Hello!
I am trying to make code for an 8080 parallel connection.
I've run into a problem very early though!
Attempting to edit the register "GPIO_OUT_REG," which, in the technical datasheet is listed as R/W capable, throws an error:

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sketch_may13a:19: error: lvalue required as left operand of assignment

   GPIO_OUT_REG|= 0b11000000000|(*readLoc);//Enable write and chip, write data

("readLoc" is a byte* pointing to the address of a uint16_t[128*128], but that's not the error here. And yes, it has been reinterpret_casted. Even writing a static value does not work.)

<Speculation>
In one of the attempts, it showed me that GPIO_OUT_REG is #defined relative to another variable:

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 #define GPIO_OUT_REG          (DR_REG_GPIO_BASE + 0x0004)

This is an issue for assignment of the variable, I'm pretty sure!
</Speculation>

[ESP_Sprite]

GPIO_OUT_REG is the memory address of the out register, not the register itself. You're supposed to use it with e.g. REG_WRITE, or alternatively use the struct defines in gpio_struct.h and do GPIO.out=0x123.

[Fuzzyzilla]

Cool! Having all of those IO functions in one place is super useful!
Thanks!