card_mode_bits
a_priv->card_mode_bits |= CM_SYSTEM_CONTROLLER_BIT;
a_priv->card_mode_bits &= ~CM_SYSTEM_CONTROLLER_BIT;
writeb(a_priv->card_mode_bits, a_priv->gpib_base + CARD_MODE_REG);
a_priv->card_mode_bits = ENABLE_PCI_IRQ_BIT;
writeb(a_priv->card_mode_bits, a_priv->gpib_base + CARD_MODE_REG);
unsigned short card_mode_bits;